It's easy: Provide a "start" sequence players must use, aka let them build on a premade replay.

That way you get around all sorts of preemptive shit, and generally if they make it into the loop, let them do it. (For example I like to make it so that the tori falls down on all four before handing over the replay. GL using your script to work your way outa' that.)

Also, rotate the fucking toris based on the players. A few degrees makes a HUGE difference. Also, ad some minor side gravity if you really wanna catch cheaters.

If nothing above suits you, PM me and ill give you the list of ideas I had back when being a part of the CET...