Thanks for posting the picture. Are you certain this is really a shutter issue? Do these trails persist at fast download speed with any exposure time including longer ones, or just shorter ones? I had trails similar to this at fast download with a previous ML16200 camera, but that was not a shutter issue. They appeared at any exposure time, and mine were worse when a bright star was positioned close to a certain dead column that ran down the middle of my FOV. When a bright star was positioned further away, the trail was less prominent. The other interesting thing was that my trails were not exactly straight but danced around a little - looked like tadpoles. Your trails are (I think) oriented along the read direction of the columns.
I sure had my share of problems with the previous camera, but I’m happy to not have those problems with the current one and let you guys have your turn.