I would like to inform, that I have had experience with Canon EOS 30V not being able to correctly space frames with BH perforations. I don't know if it is a malfunction of this specific camera model or unit or maybe the IR sensor that counts the perforations is only useable with standard still film perforations. So I don't know, if the claim that it runs fine through any camera is 100% true. I will try some HR-50 soon (also with BH perforations) to see if maybe it was a CineStill thing or not.
Welcome!
Your experience is puzzling. Two explanations come to my mind:
-) the sensor position is maladjusted, so that its rays run just at the outer edge of the hole, where the shape of holes differ. Not very convincing.
-) the sensor works erratically and just by pure coincidence failed at BH perforations.
Basically one could argue too on the IR reflectivity, transmission of the film, thus something only deliberartely related to the peforations.
