GTA III - Need Help With CLEO

I recently got GTA III during the summer sales and am trying to install some mods for the game; specifically the Mission Loader and MAP mods. These mods, however, require the use of CLEO for GTA III. I tried downloading CLEO 4 version 1.0.1.7. The problem I'm having, however, is that when I drag and drop the .cs files in the CLEO folder (which I believe is what I'm supposed to do) and run the game, the mods do not work. I am wondering if CLEO isn't supported for STEAM versions of GTA III, or if it is, what is it I'm doing wrong.

Thank you for the help.

GTA III - Need Help With CLEO