It sounds like KScan3D installed a second set of Kinect device drivers (OpenNI) without warning you.
When you have 2 sets of drivers for one piece of hardware (official Microsoft drivers, and OpenNI drivers) Windows will have to decide which ones to use when trying to talk to the hardware.
Most probably it will use the last installed.
To get Pro PointCloud working again you'll need to uninstall any references to OpenNI, PrimeSense and/or SensorKinect from the Windows Control Panel, or maybe KScan3D can uninstall it cleanly for you.
You might also need to reboot and/or reinstall the official Microsoft Kinect drivers (for example by ticking the box in the Brekel installer to auto download/install it), but then it should work again.
Greets,