diff --git a/scripts/populate_fairstore.py b/scripts/populate_fairstore.py
index 3338b35..4283b9d 100644
--- a/scripts/populate_fairstore.py
+++ b/scripts/populate_fairstore.py
@@ -210,12 +210,31 @@ async def _all_packages(client: CKANClient) -> list[dict[str, Any]]:
             return packages
 
 
+async def _all_group_rows(client: CKANClient, action_name: str) -> list[dict[str, Any]]:
+    """Read every organization or group despite portal-side page-size caps."""
+    rows: list[dict[str, Any]] = []
+    seen_ids: set[str] = set()
+    offset = 0
+    while True:
+        result = await client.action(
+            action_name,
+            {"all_fields": True, "limit": 1000, "offset": offset},
+        )
+        batch = list(result) if isinstance(result, list) else []
+        if not batch:
+            return rows
+        new_rows = [row for row in batch if str(row.get("id")) not in seen_ids]
+        if not new_rows:
+            return rows
+        rows.extend(new_rows)
+        seen_ids.update(str(row.get("id")) for row in new_rows)
+        offset += len(batch)
+
+
 async def _source_snapshot(
     client: CKANClient, *, organization: str | None = None, limit: int | None = None
 ) -> dict[str, list[dict[str, Any]]]:
-    organization_rows = await client.action(
-        "organization_list", {"all_fields": True, "include_dataset_count": True}
-    )
+    organization_rows = await _all_group_rows(client, "organization_list")
     organizations: list[dict[str, Any]] = []
     for row in organization_rows if isinstance(organization_rows, list) else []:
         if organization and row.get("name") != organization:
@@ -232,8 +251,7 @@ async def _source_snapshot(
         )
         organizations.append(full or row)
 
-    group_rows = await client.action("group_list", {"all_fields": True})
-    groups = list(group_rows) if isinstance(group_rows, list) else []
+    groups = await _all_group_rows(client, "group_list")
 
     packages = await _all_packages(client)
     if organization:
@@ -257,8 +275,8 @@ async def _source_snapshot(
 
 
 async def _target_snapshot(client: CKANClient) -> dict[str, list[dict[str, Any]]]:
-    organizations = await client.action("organization_list", {"all_fields": True})
-    groups = await client.action("group_list", {"all_fields": True})
+    organizations = await _all_group_rows(client, "organization_list")
+    groups = await _all_group_rows(client, "group_list")
     packages = await _all_packages(client)
     return {
         "organizations": list(organizations) if isinstance(organizations, list) else [],
@@ -297,7 +315,14 @@ def check(
     )
     if root_existing and str(root_existing.get("id")) != store_id:
         collisions.append(f"source-store organization {store_name!r} already exists")
-    check("organization", source["organizations"], target["organizations"])
+    if any(str(row.get("id")) == store_id for row in source["organizations"]):
+        collisions.append(f"source organization UUID {store_id!r} matches the source-store UUID")
+    # A prior run may have used the bare site ID for the synthetic root. It is
+    # renamed before source organizations are written, so exclude it here.
+    target_organizations = [
+        row for row in target["organizations"] if str(row.get("id")) != store_id
+    ]
+    check("organization", source["organizations"], target_organizations)
     # CKAN group/category names are site-wide. Reuse an existing category with
     # the same name instead of rewriting it with another portal's UUID.
     check("group", source["groups"], target["groups"], allow_shared_name=True)
@@ -332,10 +357,30 @@ def check(
 async def _write_action(
     client: CKANClient, action: str, payload: dict[str, Any], *, label: str
 ) -> dict[str, Any]:
-    result = await client.action(action, payload)
-    if not result:
-        raise MirrorError(f"{action} failed for {label}")
-    return result
+    show_actions = {
+        "organization_create": "organization_show",
+        "group_create": "group_show",
+        "package_create": "package_show",
+        "resource_create": "resource_show",
+    }
+    for attempt in range(3):
+        result = await client.action(action, payload)
+        if result:
+            return result
+
+        # A gateway can time out after CKAN commits the object. Resolve by the
+        # preserved UUID before retrying so a successful write is not treated
+        # as a failed duplicate create.
+        show_action = show_actions.get(action)
+        if show_action and payload.get("id"):
+            existing = await client.action(show_action, {"id": payload["id"]})
+            if existing:
+                return existing
+
+        if attempt < 2:
+            await asyncio.sleep(2**attempt)
+
+    raise MirrorError(f"{action} failed for {label}")
 
 
 def _resource_payload(
@@ -391,6 +436,8 @@ async def mirror_catalog(
     source_data = await _source_snapshot(source, organization=organization, limit=limit)
     target_data = await _target_snapshot(target)
     store_name = _slug(site_id, "source-store")
+    if store_name in {str(row.get("name")) for row in source_data["organizations"]}:
+        store_name = _slug(f"{store_name}-source", "source-store")
     store_id = str(uuid.uuid5(uuid.NAMESPACE_URL, source_url.rstrip("/")))
     _assert_no_collisions(source_data, target_data, store_name=store_name, store_id=store_id)
 
@@ -517,6 +564,8 @@ async def mirror_catalog(
             source_url=source_url,
             source_id=package_id,
         )
+        if not str(payload.get("notes") or "").strip():
+            payload["notes"] = "No description was provided by the source catalog."
         if not owner_org:
             payload["extras"].append({"key": "mirror_source_owner_org", "value": ""})
         exists = package_id in target_package_ids
diff --git a/tests/unit/test_fairstore_populate.py b/tests/unit/test_fairstore_populate.py
index ed6b25c..5601370 100644
--- a/tests/unit/test_fairstore_populate.py
+++ b/tests/unit/test_fairstore_populate.py
@@ -81,6 +81,38 @@ async def action(self, name, payload=None):
         return response(payload or {}) if callable(response) else response
 
 
+@pytest.mark.asyncio
+async def test_group_rows_follow_portal_page_caps():
+    rows = [{"id": str(index), "name": f"publisher-{index}"} for index in range(5)]
+
+    def capped_page(payload):
+        offset = payload.get("offset", 0)
+        return rows[offset : offset + 2]
+
+    client = FakeCKAN({"organization_list": capped_page})
+
+    result = await populate_fairstore._all_group_rows(client, "organization_list")
+
+    assert result == rows
+    assert [payload["offset"] for _, payload in client.calls] == [0, 2, 4, 5]
+
+
+@pytest.mark.asyncio
+async def test_write_action_recovers_when_gateway_times_out_after_create():
+    resource = {"id": "resource-id", "name": "Created resource"}
+    client = FakeCKAN({"resource_create": {}, "resource_show": resource})
+
+    result = await populate_fairstore._write_action(
+        client,
+        "resource_create",
+        resource,
+        label="resource-id",
+    )
+
+    assert result == resource
+    assert [action for action, _ in client.calls] == ["resource_create", "resource_show"]
+
+
 def _source_client():
     organization = {
         "id": "11111111-1111-4111-8111-111111111111",
@@ -197,6 +229,61 @@ async def test_mirror_preserves_source_identity_and_adds_hierarchy_and_qsv():
     assert "datastore_active" not in resource
 
 
+@pytest.mark.asyncio
+async def test_mirror_supplies_description_when_source_notes_are_blank():
+    source, _organization, package = _source_client()
+    package["notes"] = ""
+    target = FakeCKAN(
+        {
+            "organization_list": [],
+            "group_list": [],
+            "package_search": {"count": 0, "results": []},
+            "organization_create": lambda payload: payload,
+            "organization_patch": lambda payload: payload,
+            "package_create": lambda payload: payload,
+            "resource_create": lambda payload: payload,
+        }
+    )
+
+    await populate_fairstore.mirror_catalog(
+        source=source,
+        target=target,
+        site_id="source-store",
+        site_title="Source Store",
+        source_url="https://source.example",
+        apply=True,
+    )
+
+    dataset = next(payload for action, payload in target.calls if action == "package_create")
+    assert dataset["notes"] == "No description was provided by the source catalog."
+
+
+@pytest.mark.asyncio
+async def test_source_store_slug_does_not_replace_same_named_source_organization():
+    source, _organization, _package = _source_client()
+    source_url = "https://source.example"
+    root_id = str(
+        populate_fairstore.uuid.uuid5(populate_fairstore.uuid.NAMESPACE_URL, source_url)
+    )
+    target = FakeCKAN(
+        {
+            "organization_list": [{"id": root_id, "name": "source-publisher"}],
+            "group_list": [],
+            "package_search": {"count": 0, "results": []},
+        }
+    )
+
+    summary = await populate_fairstore.mirror_catalog(
+        source=source,
+        target=target,
+        site_id="source-publisher",
+        site_title="Source Publisher",
+        source_url=source_url,
+    )
+
+    assert summary["store_organization"] == "source-publisher-source"
+
+
 def test_preflight_rejects_dataset_name_collision_but_reuses_group_category():
     source = {
         "organizations": [],