So...

I have tried a couple of halo mods.
I have made sure they are for the one I have blah blah blah.

1: I backupped the map file.
2: I copied the new one to the MAPS folder.
3: I restarted halo.
4: I opened the map it is supposed to work in. (Rifle is supposed to spawn marines)
5: I started playing.
6: ABSOLUTELY NOTHING HAS CHANGED!!!
7: I posted this.

PLEASE help me...
Any possible reasons why it doesn't work?

PS:
I use vista