The easiest for the item bar, is to set it so it is visible on all toons, and not just the master.

And then create a Repeater Region that goes to all toons.
As in, any can click, and the slaves all click the same as the master.

Then click whatever, and they all do it.
Change any item (drag onto or off of the bar) and they mimic the activity.

I do that for quest items, armor upgrades, food buffs, flasks, etc.




As far as Numpad goes.
You cannot use several modifier keys.
And you need to be sure NumLock is in the correct state.

You could make a mapped key for the hotkey with both NumLock on and NumLock off.
That sends the same output to the window either way.
I don't generally use the number pad for hotkeys, because of NumLock on and off.