I've got Win XP, 19.12.2014 steam version of TWoM with 3DM vitamine. Tested F1 (heh works, I think ;) ) F4 (works, almost everything is doing immediately), F5 (none of items are used, everything works correctly) and F6 (day resets to 6A.M.).
I didn't test the F3 function, because it wasn't...