Have you checked the carb main jet for debris or inspected the carb diaphragm for tears?
Dyna coils have been know to fail but I haven't heard of their ignition module/booster failing for this vintage BMW.
Hope this helps.
"He had that rare weird electricity about him--that extremely wild and heavy presence that you only see in a person who has abandoned all hope of ever behaving"normally"."
"Woof, woof woof woof ...woof woof!!!!!!!!!"
Cricket the Dog-RIP