You'd be suprised how hard it is to get good, 'explaining' screencap material. I'll take your scenario into consideration, but I'd need to stage it myself.
Of course it's hard. That's why companies hire many people to do that. There's much more to it than just slapping four images together and calling it a promo.
If you want to do it good, you have to put some effort.
Also if you need people just ask.