I can see in your logs where it happens, but I don't have any insight as to why. Since I know SGPro works very nicely with Lynx and focus boss, I am guessing that it might be an issue with USB, a USB hub or the power supply (I had a problem with my power supply being loose in the socket). Whatever it is, I can see in the logs that the focuser is actually reporting that it is no longer connected. The focuser ASCOM logs would provide the other side of the story.
True... most go this route, but rest assured, we offer a 30 day, no questions refund if you don't like SGPro for any reason.