What cheats are allowed? All Techs, max money, all pages to encyclopedia? Also i need someone to please explain in detail how the tournaments work.

None that make a monster directly better... I used a money cheat just to get everything smoother. It helps indirectly, but being rich will not make your monster good. It's kind of common sense that you can't use a cheat to max out a monster... this isn't major league baseball.

Generally, nothing that affects a monster or its parents is allowed.

Back in the day, the only cheat code allowed was the one which removed the strong glue from inventory...

The tourney hosts receive saves via email and run the battles while typing the action in the chatroom. There's a transcript of the most recent event posted here in the Locker Room.