We are in the process of creating wet area mods for our master files. In most of the mods we include the interior fittings only but some optional bathroom layouts include extra walls which are included in the mod rather than the master. In the mod file these walls intersect correctly, and when the master with the linked mod is viewed in 3D the walls intersect correctly.
In 2D plan, however, the walls do not intersect correctly:
It looks like a layer number issue but I have tried adjusting the layer numbers in the mod, in the master, and in the mod master layer but nothing makes any difference. The walls are all the same composite and are set correctly for building materials, core and finish. The extra walls in the image above are set above the floor and below the ceiling to see if there was any conflict in the master from those elements, that didn't help. When I first switched the reference line to the center, everything cleaned up correctly, but after I switched to an alternative mod then back to this one, the incorrect display returned.
I should have tried linking into another file before posting - that worked. The problem was caused by overlapping alternative mods having the same layer intersection number on their master layers. I was trying to find the conflict between the master and mod when in fact the conflict occurred between two alternative mods.