I had the same problem. I have the Helix floor. Stopped at 50%, no recognition of the Helix, etc., etc. However, I've now successfully updated the Helix.
I rebooted in safe mode 6+12 (Entered Update Mode). Tried running the updater again, but it didn't see the Helix. Rebooted the Helix again whilst the updater was running and this time it saw the Helix. I was then able to successfully able to complete the update.
I am not convinced that changing ports, uninstalling, etc. solves the problem. I think it's just trying multiple attempts until it works and people are assuming that the changes they've enacted are causing it to work.