it's about two years old, so maybe it's time to find a fix now.Maybe, yes :-). At least it seems mostly harmless.
i hope it is fixed now in git.
please submit a bug report on savannah. you can attach the texture to the bug if necessary.Build-extrusion has some more issues, I noticed. ... I have a example of this, forming a bottle with a label, but the lable texture is a bit bigger than what I'd send to the list.
best, gabor
