PL2303 is needed as the Shoestring EQDIR is having a Serial Port on both sides like the attached one
Installed KStars and there I can connect to the mount using the local mode in the device manager.
Now what is missing when trying to connect via CdC?
Not sure if I read somewhere that I need to enter GPS data before being able to connect to the mount via EQMOD. Could the issue be in this area?