Added code to screen out unusable keys in the case of "hotkey,then press a key" actions. If the key is not in 1 - 9 and is not in list of letters for sections, (such as t,b,l,r,s,c,h,v,u,z) a "ding" is played (unless the key in the Esc key. In which case the function returns silently, as that's the valid key to cancel an operation.)
It may seem like a lot of particulars.. but it's kind of like the vi
editor. If you use it fairly regularly, before you know it your fingers remember what to do.