these files are 3d mesh or 2d texture.
How convert mesh or texture?
here's few samples
.rif
https://www.mediafire.com/file/bimokwug ... 0.rif/file
https://www.mediafire.com/file/96bugxuw ... 2.rif/file
https://www.mediafire.com/file/5c3ptyzz ... 8.rif/file
https://www.mediafire.com/file/fbsfu3hh ... 4.rif/file
.seek
https://www.mediafire.com/file/xkk28pdz ... .seek/file
https://www.mediafire.com/file/6do872yv ... .seek/file
https://www.mediafire.com/file/yba3bg9t ... .seek/file