Update!
If your running your Cubase as admin, along with anything like jBridge etc… untick all the apps your using “run as administrator” and then apply Full Control permissions to each of the program folders to your user account. (Right click program folder and click properties then the security tab)
Then load Regedit and goto HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Policies\System
and change UAC Enabled: 1 to UAC Disabled: 0, then Reboot!
This will resolve all your drag and drop problems.