OK, my cluelessness doesn't seem to be inspiring many posts.
Anyway, I have the balance wheel off and am trying to get a peek at the stop lever to see where it is and, as per an old post by The Zigmeister, see if I can 'jiggle' it back into position. Problem is I am having trouble seeing anything that resembles a stop lever... I'll keep stumbling along, but any advice is much appreciated.