I love the game and atmosphere. Is there any actual rule that forbids placing any card on empty slot? I don't know the real card game rules. I was a big fan of "DChoc Cafe Solitaire" in mobile java days, and I can't remember there was such limit.
Yeah, on the foundation (top 4 slots) you need to build up from A to K, and on the tableau (bottom 7 slots) you build down from K to A!