Well, SCMDraft homepage refuses to send me an activation email, so I'll post it here. Durning the making of my last map I've faced a problem that some walkable/buildable doodads for Ice Tileset (like car wheel trail thing) become unbuildable in SCMDraft. While this is not serious, it is somewhat bad for map decoration.
Also, SCMDraft sometimes screws mineral-nexus buildability so it takes 4 squares instead of 3, but I'm sure that has been reported already.
SCM Draft also sometimes bugs your maps so you can't open them neither in SCM Draft or any other Editor. That's why I always save the maps I edited with SCM as a new File.
Hehe, I have about 15 different builds of my last map. =) Always save a new build as a new file is a golden rule of all software creation, be it programming, mapmaking or any other. =)