BenRierimanu

Material Swaps are ignored in precombine generation due to a bug in certain situations. There's an xEdit script floating around to work around this. PJM's scripts (the set used in building PRP) have this functionality built in.

I think it's a vanilla bug, you can see the gap bug in many places around the commonwealth (like Diamond City ext, behind the columns) In my experience when dealing with these narrow gaps, I think it's floating point related calculation errors. Known issue with the CK, and I'm trying to patch them as I see them. (The refs usually just need a subtle nudge to work around it.)

Did you ever get clean builds working?