I though if you use mosfets you didnt have to use resistors,
Wrong, a FET gate looks like a capacitor, when a capacitor is discharged it looks like a short circuit, you need something to limit this current to protect your arduino. I would go with a 100R resistor here, not 22K as that will slow down the FET turn on and increase the heat the FET produces.
It will however not stop it from working so it is not the problem you are looking for.
So forget trying to use other people's code and just write something to control one colour at a time. Then you can isolate if you have a hardware fault or a software one.