Again, an electrical problem that only manifests itself at some mid-range RPM is a very unusual occurrence. In fact, I can't think of how that could happen unless it is related to a poor connection/vibration but per your last post, you checked all the connections.
OTOH, I suppose it could be the e-ignition itself - some fault internally that is causing the problem. Not sure what sort of fault could cause that but there are various components/chips in there that could fail in some odd way that mortals do not understand and produce who-knows-what kind of symptoms!
So I guess swapping the E-ignition with another one would be worth trying.
It might have been covered, if so, I apologize - does the misfire occur while in neutral at the RPM range in question or only under load (riding the bike)?