diff --git a/deltatech_picking_transit/README.rst b/deltatech_picking_transit/README.rst
index be330e2b5..1d4e86a6a 100644
--- a/deltatech_picking_transit/README.rst
+++ b/deltatech_picking_transit/README.rst
@@ -49,6 +49,27 @@ Features:
 .. contents::
    :local:
 
+Changelog
+=========
+
+18.0.0.0.15
+-----------
+
+- Setup on install: create a per-company transit stock location and, on
+  each warehouse, a two-step delivery operation type (with automatic
+  second transfer) and a two-step reception operation type, wired to the
+  warehouse main stock location and the transit location. Runs only at
+  install, so databases already using the module are not affected.
+- The second transfer can now be created manually only after the first
+  transfer is validated, so the goods are actually in the transit
+  location.
+- The second transfer now inherits the quantity actually moved to
+  transit, so the flow works even when the operator filled only the
+  "Quantity" field and left the "Demand" at 0.
+- Fixed the ``is_transit_transfer`` and ``sub_location_existent``
+  computes to work on multi-record sets (no more singleton errors) and
+  removed the side effect from the compute method.
+
 Bug Tracker
 ===========
 
diff --git a/deltatech_picking_transit/__init__.py b/deltatech_picking_transit/__init__.py
index 9b4296142..700d6ab98 100644
--- a/deltatech_picking_transit/__init__.py
+++ b/deltatech_picking_transit/__init__.py
@@ -1,2 +1,3 @@
 from . import models
 from . import wizard
+from .hooks import post_init_hook
diff --git a/deltatech_picking_transit/__manifest__.py b/deltatech_picking_transit/__manifest__.py
index a85abb84c..4429b266f 100644
--- a/deltatech_picking_transit/__manifest__.py
+++ b/deltatech_picking_transit/__manifest__.py
@@ -1,6 +1,6 @@
 {
     "name": "Stock Auto Transfer",
-    "version": "18.0.0.0.14",
+    "version": "18.0.0.0.15",
     "author": "Terrabit, Voicu Stefan",
     "website": "https://www.terrabit.ro",
     "category": "Warehouse",
@@ -14,6 +14,7 @@
         "views/stock_picking_type_view.xml",
     ],
     "development_status": "Beta",
+    "post_init_hook": "post_init_hook",
     "maintainers": ["VoicuStefan2001"],
     "images": ["static/description/main_screenshot.png"],
 }
diff --git a/deltatech_picking_transit/hooks.py b/deltatech_picking_transit/hooks.py
new file mode 100644
index 000000000..8bf196e9e
--- /dev/null
+++ b/deltatech_picking_transit/hooks.py
@@ -0,0 +1,81 @@
+# hooks.py
+
+from odoo import _
+
+
+def post_init_hook(env):
+    """Set up the two-step transit configuration on a fresh install.
+
+    Runs only at install time (never on module update), so databases that
+    already use this module are left untouched. For every company it creates a
+    dedicated transit stock location and, on each of the company warehouses, a
+    two-step delivery operation type (with automatic second transfer) and a
+    two-step reception operation type, wired to the warehouse main stock
+    location and the transit location.
+    """
+    for company in env["res.company"].search([]):
+        _setup_company_two_step_transit(env, company)
+
+
+def _setup_company_two_step_transit(env, company):
+    Location = env["stock.location"].with_company(company)
+    PickingType = env["stock.picking.type"].with_company(company)
+
+    parent_location = env.ref("stock.stock_location_locations", raise_if_not_found=False)
+    transit_location = Location.create(
+        {
+            "name": _("2-Step Transit"),
+            "usage": "transit",
+            "location_id": parent_location.id if parent_location else False,
+            "company_id": company.id,
+        }
+    )
+
+    warehouses = env["stock.warehouse"].search([("company_id", "=", company.id)])
+    for warehouse in warehouses:
+        stock_location = warehouse.lot_stock_id
+
+        # Two-step delivery: warehouse stock -> transit, with automatic
+        # creation of the second (reception) transfer on validation.
+        if not _has_two_step_type(PickingType, warehouse, "delivery"):
+            PickingType.create(
+                {
+                    "name": _("2-Step Delivery"),
+                    "code": "internal",
+                    "sequence_code": "2SD",
+                    "warehouse_id": warehouse.id,
+                    "company_id": company.id,
+                    "default_location_src_id": stock_location.id,
+                    "default_location_dest_id": transit_location.id,
+                    "two_step_transfer_use": "delivery",
+                    "auto_second_transfer": True,
+                }
+            )
+
+        # Two-step reception: transit -> warehouse stock.
+        if not _has_two_step_type(PickingType, warehouse, "reception"):
+            PickingType.create(
+                {
+                    "name": _("2-Step Reception"),
+                    "code": "internal",
+                    "sequence_code": "2SR",
+                    "warehouse_id": warehouse.id,
+                    "company_id": company.id,
+                    "default_location_src_id": transit_location.id,
+                    "default_location_dest_id": stock_location.id,
+                    "two_step_transfer_use": "reception",
+                }
+            )
+
+
+def _has_two_step_type(PickingType, warehouse, use):
+    return bool(
+        PickingType.search(
+            [
+                ("warehouse_id", "=", warehouse.id),
+                ("code", "=", "internal"),
+                ("two_step_transfer_use", "=", use),
+            ],
+            limit=1,
+        )
+    )
diff --git a/deltatech_picking_transit/models/stock_picking.py b/deltatech_picking_transit/models/stock_picking.py
index fcc258d44..3c11d526e 100644
--- a/deltatech_picking_transit/models/stock_picking.py
+++ b/deltatech_picking_transit/models/stock_picking.py
@@ -19,8 +19,16 @@ class StockPicking(models.Model):
     )
 
     def open_transfer_wizard(self):
+        self.ensure_one()
         if self.second_transfer_created:
             raise UserError(_("Second transfer already created."))
+        if self.state != "done":
+            raise UserError(
+                _(
+                    "Validate this transfer first. The second transfer can only be "
+                    "created after the goods have arrived in the transit location."
+                )
+            )
         return {
             "name": "Create Transfer",
             "type": "ir.actions.act_window",
@@ -48,7 +56,7 @@ def create_second_transfer_wizard(self, final_dest_location_id, picking_type_id)
                 new_picking.action_confirm()
                 # new_picking.action_assign()
                 # new_picking.do_unreserve()
-                self.second_transfer_created = True
+                picking.second_transfer_created = True
 
                 message = _("This transfer was generated from %s.") % picking.name
                 new_picking.message_post(body=message)
@@ -62,15 +70,22 @@ def create_second_transfer_wizard(self, final_dest_location_id, picking_type_id)
                 return new_picking
 
     def copy_move_lines(self, source_picking, target_picking):
-        for move in source_picking.move_ids_without_package:
-            move.sudo().copy(
-                {
-                    "picking_id": target_picking.id,
-                    "location_id": source_picking.location_dest_id.id,
-                    "location_dest_id": target_picking.location_dest_id.id,
-                    "state": "draft",
-                }
-            )
+        moves = source_picking.move_ids_without_package
+        if not moves:
+            return
+        default = {
+            "picking_id": target_picking.id,
+            "location_id": source_picking.location_dest_id.id,
+            "location_dest_id": target_picking.location_dest_id.id,
+            "state": "draft",
+        }
+        vals_list = moves.sudo().copy_data(default)
+        for move, vals in zip(moves, vals_list):
+            # the second transfer must move what actually arrived in transit:
+            # use the done quantity so the flow still works when the operator
+            # filled only the "Quantity" field and left the "Demand" at 0
+            vals["product_uom_qty"] = move.quantity or move.product_uom_qty
+        self.env["stock.move"].sudo().create(vals_list)
 
     # @api.model
     # def create(self, vals):
@@ -80,6 +95,7 @@ def copy_move_lines(self, source_picking, target_picking):
     #        # res.immediate_transfer = False
     #     return res
 
+    @api.depends("picking_type_id")
     def _compute_sub_location_existent(self):
         for record in self:
             sub_location_usage = (
@@ -87,7 +103,7 @@ def _compute_sub_location_existent(self):
                 .sudo()
                 .get_param(key="deltatech_picking_transit.use_sub_locations", default=False)
             )
-            if sub_location_usage and self.picking_type_id.code == "internal":
+            if sub_location_usage and record.picking_type_id.code == "internal":
                 record.sub_location_existent = True
             else:
                 record.sub_location_existent = False
@@ -104,18 +120,21 @@ def reassign_location(self):
             if quants:
                 move_line.location_id = quants[0].location_id
 
-    @api.onchange("picking_type_id")
+    @api.depends("picking_type_id", "second_transfer_created")
     def _compute_is_transit_transfer(self):
         for record in self:
-            if self.second_transfer_created:
-                record.is_transit_transfer = False
-                return
-            if record.picking_type_id.code == "internal" and record.picking_type_id.two_step_transfer_use == "delivery":
-                record.is_transit_transfer = True
-                record.action_toggle_is_locked()
-            # record.immediate_transfer = False
-            else:
-                record.is_transit_transfer = False
+            record.is_transit_transfer = bool(
+                not record.second_transfer_created
+                and record.picking_type_id.code == "internal"
+                and record.picking_type_id.two_step_transfer_use == "delivery"
+            )
+
+    @api.onchange("picking_type_id")
+    def _onchange_picking_type_lock_transit(self):
+        # lock the transit transfer so the move lines cannot be edited before
+        # the second transfer is generated
+        if self.is_transit_transfer:
+            self.action_toggle_is_locked()
 
     def button_validate(self):
         for picking in self:
diff --git a/deltatech_picking_transit/readme/HISTORY.md b/deltatech_picking_transit/readme/HISTORY.md
new file mode 100644
index 000000000..bf32628c9
--- /dev/null
+++ b/deltatech_picking_transit/readme/HISTORY.md
@@ -0,0 +1,15 @@
+## 18.0.0.0.15
+
+- Setup on install: create a per-company transit stock location and, on each
+  warehouse, a two-step delivery operation type (with automatic second transfer)
+  and a two-step reception operation type, wired to the warehouse main stock
+  location and the transit location. Runs only at install, so databases already
+  using the module are not affected.
+- The second transfer can now be created manually only after the first transfer
+  is validated, so the goods are actually in the transit location.
+- The second transfer now inherits the quantity actually moved to transit, so
+  the flow works even when the operator filled only the "Quantity" field and
+  left the "Demand" at 0.
+- Fixed the `is_transit_transfer` and `sub_location_existent` computes to work
+  on multi-record sets (no more singleton errors) and removed the side effect
+  from the compute method.
diff --git a/deltatech_picking_transit/static/description/index.html b/deltatech_picking_transit/static/description/index.html
index 521a41f1a..40aae76f4 100644
--- a/deltatech_picking_transit/static/description/index.html
+++ b/deltatech_picking_transit/static/description/index.html
@@ -396,31 +396,57 @@ <h1 class="title">Stock Auto Transfer</h1>
 <p><strong>Table of contents</strong></p>
 <div class="contents local topic" id="contents">
 <ul class="simple">
-<li><a class="reference internal" href="#bug-tracker" id="toc-entry-1">Bug Tracker</a></li>
-<li><a class="reference internal" href="#credits" id="toc-entry-2">Credits</a><ul>
-<li><a class="reference internal" href="#authors" id="toc-entry-3">Authors</a></li>
-<li><a class="reference internal" href="#maintainers" id="toc-entry-4">Maintainers</a></li>
+<li><a class="reference internal" href="#changelog" id="toc-entry-1">Changelog</a><ul>
+<li><a class="reference internal" href="#section-1" id="toc-entry-2">18.0.0.0.15</a></li>
 </ul>
 </li>
+<li><a class="reference internal" href="#bug-tracker" id="toc-entry-3">Bug Tracker</a></li>
+<li><a class="reference internal" href="#credits" id="toc-entry-4">Credits</a><ul>
+<li><a class="reference internal" href="#authors" id="toc-entry-5">Authors</a></li>
+<li><a class="reference internal" href="#maintainers" id="toc-entry-6">Maintainers</a></li>
 </ul>
+</li>
+</ul>
+</div>
+<div class="section" id="changelog">
+<h1><a class="toc-backref" href="#toc-entry-1">Changelog</a></h1>
+<div class="section" id="section-1">
+<h2><a class="toc-backref" href="#toc-entry-2">18.0.0.0.15</a></h2>
+<ul class="simple">
+<li>Setup on install: create a per-company transit stock location and, on
+each warehouse, a two-step delivery operation type (with automatic
+second transfer) and a two-step reception operation type, wired to the
+warehouse main stock location and the transit location. Runs only at
+install, so databases already using the module are not affected.</li>
+<li>The second transfer can now be created manually only after the first
+transfer is validated, so the goods are actually in the transit
+location.</li>
+<li>The second transfer now inherits the quantity actually moved to
+transit, so the flow works even when the operator filled only the
+“Quantity” field and left the “Demand” at 0.</li>
+<li>Fixed the <tt class="docutils literal">is_transit_transfer</tt> and <tt class="docutils literal">sub_location_existent</tt>
+computes to work on multi-record sets (no more singleton errors) and
+removed the side effect from the compute method.</li>
+</ul>
+</div>
 </div>
 <div class="section" id="bug-tracker">
-<h1><a class="toc-backref" href="#toc-entry-1">Bug Tracker</a></h1>
+<h1><a class="toc-backref" href="#toc-entry-3">Bug Tracker</a></h1>
 <p>Bugs are tracked on <a class="reference external" href="https://www.terrabit.ro/helpdesk">Terrabit Issues</a>.
 In case of trouble, please check there if your issue has already been reported.</p>
 <p>Do not contact contributors directly about support or help with technical issues.</p>
 </div>
 <div class="section" id="credits">
-<h1><a class="toc-backref" href="#toc-entry-2">Credits</a></h1>
+<h1><a class="toc-backref" href="#toc-entry-4">Credits</a></h1>
 <div class="section" id="authors">
-<h2><a class="toc-backref" href="#toc-entry-3">Authors</a></h2>
+<h2><a class="toc-backref" href="#toc-entry-5">Authors</a></h2>
 <ul class="simple">
 <li>Terrabit</li>
 <li>Voicu Stefan</li>
 </ul>
 </div>
 <div class="section" id="maintainers">
-<h2><a class="toc-backref" href="#toc-entry-4">Maintainers</a></h2>
+<h2><a class="toc-backref" href="#toc-entry-6">Maintainers</a></h2>
 <p>Current maintainer:</p>
 <p><a class="reference external image-reference" href="https://github.com/VoicuStefan2001"><img alt="VoicuStefan2001" src="https://github.com/VoicuStefan2001.png?size=40px" /></a></p>
 <p>This module is part of the <a class="reference external" href="https://github.com/dhongu/deltatech/tree/18.0/deltatech_picking_transit">dhongu/deltatech</a> project on GitHub.</p>
diff --git a/deltatech_picking_transit/views/stock_picking_views.xml b/deltatech_picking_transit/views/stock_picking_views.xml
index b167b4f04..eba4fe970 100644
--- a/deltatech_picking_transit/views/stock_picking_views.xml
+++ b/deltatech_picking_transit/views/stock_picking_views.xml
@@ -21,7 +21,7 @@
                     type="object"
                     string="Create Transfer"
                     class="btn-primary"
-                    invisible="is_transit_transfer==False or origin!=False or create_second_transfer_automatically==True"
+                    invisible="is_transit_transfer==False or origin!=False or create_second_transfer_automatically==True or state!='done'"
                 />
             </xpath>
         </field>