Quoting RyderOCZ

Roger

1st thing to do: rcon_password "insert password Prime sends you" without the quotes

Then you must procede any command with "rcon"

rcon changlevel {insertlevelnamehere} without the brackets. Note: the level name must be the proper name for the map, so:
tc_hydro
cp_well
cp_granary
cp_dustbowl
cp_gravelpit
ctf_2fort

status = lists all players (userid, name, uniqueid (steamid) connected (time) ping loss stat adr) it is kind of hard to read, but you should do that first so you can see who to kick.
rcon users = alternate way to display users on server instead of above
rcon kick "playersname" = kicks user off server (you have to use quotes, based on what I have found on the net)
rcon kickban "playersname" = kicks and bans

That is a short list