[4] Fix collection_order

VERSION

@@ -1 +1 @@
-1.18.1-develop3
+1.18.1-develop4

modules/builder.py

@@ -690,8 +690,8 @@ class CollectionBuilder:
                     if ts not in sorts:
                         raise Failed(f"{self.Type} Error: collection_order: {ts} is invalid. Options: {', '.join(sorts)}")
                     self.custom_sort.append(ts)
-            if not self.custom_sort:
-                raise Failed(f"{self.Type} Error: {test_sort} collection_order invalid\n\trelease (Order Collection by release dates)\n\talpha (Order Collection Alphabetically)\n\tcustom (Custom Order Collection)\n\tOther sorting options can be found at https://github.com/meisnate12/Plex-Meta-Manager/wiki/Smart-Builders#sort-options")
+            if test_sort not in plex.collection_order_options + ["custom.asc", "custom.desc"] and not self.custom_sort:
+                raise Failed(f"{self.Type} Error: {test_sort} collection_order invalid\n\trelease (Order Collection by release dates)\n\talpha (Order Collection Alphabetically)\n\tcustom.asc/custom.desc (Custom Order Collection)\n\tOther sorting options can be found at https://github.com/meisnate12/Plex-Meta-Manager/wiki/Smart-Builders#sort-options")
 
         if self.smart:
             self.custom_sort = None