The hmt_with_pluigins.rar file you have requested: Tools and Utilities / Modding Tools / HMT with Plugins - 1.32mb is not available. Perhaps try browsing all files for the game Halo: Combat Evolved and upload any files you want to share or are missing. This is the only information we could locate:
HMT lets you mod and edit Halo 1 pc. It lets you make weapons infinite ammo, do pmi and much more. Since this has plugins, it lets you do much more than normal hmt does.