[Captain_McCusker]

If you can make changes to the config file, that's about the only way. If you're at a remote location from your server, you'll need FTP access to the main dir. Open the config file (server.cfg was my default config, but the extension is .cfg in any case) using Notepad and the map rotation will look something like this:

seta sv_maplist "obj/obj_team1 obj/obj_team2 obj/obj_team4"
map obj/obj_team1

The first line is your rotation and the second is the first map the server will use when it starts.

Hope that helps you out some.