By some miracle, I just met with success. Instead of using a .blend file, I imported a .3ds file that I made in a different program. After that, everything worked perfectly. The .3ds file exported back out just fine, and I exported the .igs file with all the scene info in it. If anyone can tell me why this is happening, I would greatly appreciate it.

Oh, and I've got Indigo running right now. Let you all know how it turns out.

It is better to do one thing well, than to do many things and excel at nothing.