same Problem here. Pix4d and Ctrl+Dji installed but no Connection to the drone.
It may be beacuse DJI GO is the default app for the 4pro+ Remote Control. When connecting the Drone and RC via microUSB the app “sees” the drone but you can’t fly like that.
So far neither DJI nor Pix4D support could help with a solution. Has anybody managed to solve the issue?
Plan B is to exchange the RC for the RC of the 4pro and get a tablet/smartphone.