Originally Posted by
ports_9144796
I think I've resolved this one my own:
"Disable cleanup between external references and the host drawing: Open the file you are externally referencing, and edit the Wall Cleanup Group Definition(s) you are using. On the Manage ribbon tab, on the Style & Display panel, select the Style Manager tool. Expand the Architectural Objects node below that drawing file, and the Wall Cleanup Group Definitions node as well. Select each definition in turn and, on the Design Rules tab, uncheck the Allow Wall Cleanup between host and xref drawings toggle. OK back out to the drawing, save the file and then reload it in the upper floor file. The Walls in that file should no longer be trying to cleanup with the Walls in the externally referenced file."