Also, I'm working on some updates to the model editing part of Editor so you can change textures on the fly. The reason is transparent polygons. Most modern games (you can google and see this) try to get you to either stay away from a lot of transparencies (just use a lot of polygons instead) or if you have transparencies, make sure to split them into distinct textures so the engine can optimize them (dim3 does this.) To that end, I'll put together the features to allow you to split up your models into opaque textures and transparent textures.
Here's an interesting write-up: http://www.sjbaker.org/steve/omniv/alpha_sorting.html
What this doesn't tell you is modern shader hardware does NOT like having discarded pixels (i.e., cut-outs.) It's why it doesn't exist in dim3, because it's been removed from OpenGL ES. The modern hardware like to do things in parallel and think that every shader pixel will hit the screen, in one way or another. So any kind of alpha cut-out actually slows EVERYTHING way down. Any kind of transparent does that too, as it can no longer use the Z-buffer.
That said, people want transparency, so I'm going all out for it ... That's why modern GPUs have so much throughput. Don't make bars with alpha, just render every bar with a hundred polygons!