@eee69wef
You have to decompile the chkn's assets.
Chkn's are file archives filled with CAL3D assets.
CAL3D assets come in 5 types: XRF, XPF, XMF XSF, XAF
For each type of CAL3D asset inside of the chkn, there is a decompiler you can run:
buysell/black_market_index.php?mode=search&question=decompiler