when it comes to your last question, i have nothing, sorry man
but to make the revert a battle command, go down to "battle layout" in your database, look at that menu to the right that says "default battle commands", and press set. make the battle command, and set the archetype to "link to event."
then go to the Monster Groups tab and make a demo party. (This isn't required, but recommended anyhow
) go down to "battle events" and set the trigger to when whoever uses whatever.
This system, while it works, can prove quite tedious, as you'd need to make a separate page for every digimon you'd like to evolve. Be sure you're happy with your system before you do anything with it though, because this needs to be on every monster group you create and that makes editing boring and annoying.
In the meantime, when it comes to your other question, perhaps you can try a common event? that's all i got