This mod is made for SA-MP 0.3d and above, it adds 5 new maps for the multiplayer:
mp_toujane
mp_carentan
mp_dawnville
mp_burgundy
mp_railyard

The gametype for these maps is DM. When you connect, a dialog will appear to choose weapons, and after if you are bored on the map you can make a vote for another one.

If you can script in SA-MP, you can rewrite the mod to any other gametype, or change the first map that loads when the server starts.