Hot keys:

i) A hot-key window passing on the hot key passes the key to the next
hot-key window down in the stack. This, of course, can lead to an infinite
loop if hot key windows cycle themselves when passing on their hot keys. DO
NOT REOPEN YOUR HOT-KEY WINDOW IN THIS WAY.

ii) If the hot key window is closed when it processes the hot key, then the
key will be started at the top of the window stack again.

iii) Applications which don't know about a late enough version of the Wimp
will have their hot-key windows made hidden. Applications which do know
about a late enough version of the Wimp can show their hot-key windows by
setting the 'hide window' bit:
Window hidden = hide window :EOR: wf_grabkeys

