for some reason, every single character folder you have has a space or a "." in the name. i have 49 character folders, and they're all fine except for some glitched up ulala character i need to fix. pick one character folder and fix its name. take the others until you find out if that's the problem.
i don't have this file. probably doesn't matter...."Characters\default\CVS\Tag"
ok, ignore all that. seems like it's the model.txt files. perhaps the folders you have are too new to work on a version this outdated. sucks, but you'll have to find older characters for now.
[Edit] yes, the model.txt files in your folders use a "vram" bmp sheet. it has all the color character parts on it, and i guess the vram sheet is cut up where it's needed when the new stepmania accesses it. the older character folders (like mine) don't do this. it does it the hard way. it seems easier to program, but it's totally useless for this port.