I don't know if this is right, but bone files are just files of your character's bones, you don't use them, every time you go to that level, the game automatically uses the bones.
To use the files, in your IVAN game directory there will be a folder called "bones", you can zip them and give them out or you can download bone files from people and then put them in your folder.
Ok so what does the [CG] stand for?
and if i wanted to make one i would do a level and then save, or would i step out of the starting place and then save and upload?