I posted a similar topic when trying to fix my slow download speeds with this camera with a view to finding a solution. After much research, experimentation and cost I haven’t found a solution - the best download speed I get with an i5 laptop and powered hub is 11 seconds.
If I use NINA the download is just a few seconds so I am coming to the conclusion that the problem lies in SGP/ASCOM, and probably the latters driver.
So, before I give up, or go to NINA, I just wondered what sort of download others are achieving with this camera?