Color choice works, abilities don't go on stack

withColorChoice pops up a lovely little windows in the browser, which
seems to work so far. I stopped putting abilities on the stack because,
first of all, it is incorrect for mana abilities, and second, it is just
annoying to go through the trouble while playing. This mostly means that
I need to find a better strategy, because this would be bad for things
like Monstrous.