Most have a commands list ingame - for example the one i've been playing on recently that runs cops and robbers, you do /msg commands and it gives you a list of commands.
There's usually an admin or someone that will help around so just ask on the server.
1) To change the map (assuming you mean between gta3 and vc) you need to edit the mtaserver.conf file. Either in notpad or you can download the editor program - http://www.mtavc.com/downloads.php?file_id=75
2) To change the gametype (between stunt and deathmatch - vc only) it is also in the mtaserver.conf file
btw there is no traffic as it would be way too difficult and stuff to sync for everyone
I think there might be a problem with the ping checker/kicker.
On a server that i use quite a bit the !ping command always brings up an average of 0 and this means the ping kicker can't work (i think it works by the average..)
It is the latest version; 2.31
Either just do Ctrl + C on all of that and paste it in and it works or dark, you could change it, use %s instead of spaces... e.g: http://www.thegamersalliance.com/freefo ... rt%201.wmv
In the filters on the left, under version tick 0.41. Or if you're filters haven't updated either update them or tick other. Then you should find some 0.41 servers.