With the Dyna triggers, the "dropping cylinders" problem is usually related to not having the gap (i.e., distance between the trigger magnet and face of the pickup) set properly. Usually, setting this right will make for nice, even spark. So, study your installation carefully, make sure this gap is even between the triggers. It may even tell you what the gap should be on the modern installation instructions: we used to have to guess at it, back in the '80s.