The compcubeif.7z file you have requested: Mods / Added Content / Weighted Companion Cube - 3.17mb is not available. Perhaps try browsing all files for the game Star Wars: Knights of the Old Republic and upload any files you want to share or are missing. This is the only information we could locate:
This is just a simple cosmetic mod which will add a talking placeable to the game. Try it out for a better idea of exactly how it works (just keep in mind that once placed, it is not removable).