The best way to run QHY8 using MaximDL is to run the ASCOM drivers.
To install the ascom drivers effectively you must remove all previous installed drivers. Do this in the control panel, programs and features menu. Then install the system drivers, then the Ascom drivers. Best available from Toms site.
http://www.astrosoft.be . He has information on how to remove the old drivers from your computer on the site also.
Remember to install the system drivers with the camera unplugged and only plug the camera in once the system setup is complete.
Good luck.