The first time I drilled the right side canopy roller, I used a drill press because I thought it would be more precise. Unfortunately, it wasn't easy to keep the part in position, and there's no tactile "feel" of what you're doing when you use a drill press. As a result, the drill bit walked a bit as it began the hole, and I ended up with a slightly offset hole through the shaft of the roller. This meant that the roller was riding slightly crooked in the rail.
I ordered a new roller shaft the week before Van's bankruptcy announcement, and it arrived the day of the announcement. Lucky timing
Today, I remedied the issue by drilling the holes again, this time with some titanium bits in a hand-held drill. It worked beautifully. Now the canopy should glide open and shut like the weapons-bay doors on an F-35.