Looks like the format is described here, it shouldn't be too terribly hard to make a program for extracting the images, though it's worth a check around to see if some such program exists already.
EDIT: This folder's KLBToolHost.exe looks promising as far as tools go, but I can't test for myself. If the program doesn't work or you want me to look at the .texb files myself, I'd be happy to.
EDIT: This folder's KLBToolHost.exe looks promising as far as tools go, but I can't test for myself. If the program doesn't work or you want me to look at the .texb files myself, I'd be happy to.