DPG gives good suggestions in his last post.Thank you Avo and DPG for your very helpful replies! It will probably be a few weeks before I can get the replacement Dynaohm and have an opportunity to try testing/rebuilding, but I will come back here either with a success story--or more questions! Thanks so much!
Just to reiterate, don't wire it up as your original drawing back in post #1. You need 20mA through each string of lamps, so however many you end up with in series, four or six, have a Dynaohm for each string. Perhaps they'll give you a loyalty discount
Best wishes for getting it all working!