When I try to add all of the textures in a folder containing MBP textures, it crashes, and when I re-open Constructor, I see that it has put only a small amount into the album. If I split the textures to another folder, it only loads an even smaller amount of those. If I attempt to add any MBG textures into an album however, it works just fine.
An addon for MB or program that would add a new world editor mode/program for a fully-functioning interior editor would be tremendous (and a pipe dream).