Most of this is basic stuff, but I'll state it here for clarity.

No actions that would get you VAC banned.
No gamechanging exploits. This includes, but is not limited to:
Skipping cresendos.
Forcing the Director to act in a certain way that gives one side an advantage.
Any form of bug that may give a player an advantage.

All matches must be played on Confogl 2.1.6/7
Matches must end with both sides taking a screenshot of the end score and uploading it to a file sharing website.
All players must record a demo fo the match using the playdemo demoname command/ These only have to be uploaded if there is a complaint about behaviour during the match.
No trash talking during the match. This is a fun event, so no bad blood

Any breaking of the rules will result in anything from a warning to a disqualification. Common sense will be used.