The mod is pretty much Classic Battletech but put into more of TA's scale of battle. it supposed to feel and emulate most of the classic battle tech universe yet still be a fun rts like TA, with the obvious restrictions of the TA engine. Right now it is in beta testing phase, and there are 2 factions. inner sphere and clan, 2 tiers light and medium. The last tier is being worked on now which which will have the heavies and assault class mechs, vehicles, and air support. It will probably be included in the next release. After its release I will probably fill in a few holes with some more units to help game play and balance.
Just unzip right into the total folder and use the custom EXE to play! Make sure you get rid of all previous mechwars or total battle tech folders, before installing, such as custom exe's, mwo, or mwp files.