If Multi Mod Manager does not load, you probably do not have cIOS. MMM is set to load ios250, if you don't have it, it will crash.
If you are having trouble with it and you think you have cIOS, run CB2_BB_SysCheck_1.6.1.zip from loadmii verify that you have cIOS by viewing the cvs report. You can post it here if you need help.
You can configure MMM to load any ios you like, just edit sd:\mmmconfig.txt to suit your needs.