Since the buttons on the LCD (additional buttons) are now saved in the order specified, how would a third page work? how would they fit into the ordering on the additional buttons screen?

The issue with propagation now that there is a specific command order is: where exactly do the propagated commands go? If a command is position 1 in one activity, does it get position 1 in every other activity? does it overwrite the existing command? Or bump all commands down, changing the ordering you initially specified?

I don't think command ordering and automatic button propagation can co-exist.