HaloMods "Classic" Read-only Archive

Ok, when I try to open up glabals.matg, (in ch2r....so i can add maps to the mainmenu), an error occurs. This is what it says:
An unhandled Exception has occured in your application. If you click continue, the application will ignore this error and attempt to continue. If you click quit, the application will be shut down immediately.

Exception has been thrown by the target of an invocation.

Now I don't know what this is, so if you guys could help me out, thanks.

Try reinstalling the program, if not, get an older version, or just use Serenity/Insolence, they work quite easily.

Ah new programs! Thanks man. I'll try them out!

No problem, and here's how to add maps:
http://files.halomods.com/viewtopic.php?t=31955

Hmm how do I do it in Serenity? It says mainmenu but........I don't know.