The double-space thing might be related to line feeds. I think there's a command in BB-Edit that strips them out, or maybe it's the "zap gremlins" command (yes, there is such a command). When you run a bvh file with a blank icon through Maconverter, you get the same kind of action as with obj files - it becomes a Windows text file (TEXT, mdos) with one of those blue PC icons. BVH files seem to work as long as they're (TEXT, mdos) or (TEXT, ttxt).