A little bit more to this, to make it go correct you have to move one of the brushes after building (breaking the “build”)
But then you build it and it happens again.
Example of why its a problem:
I have say, 5 blocks stacked,
each with a differnt mat
works fine, then once i build, i can no longer set separate mat’s on each block or adjust the position of the mats as it thinks the section is one big face…