It runs the compatibility test for a few seconds, it says test ok, but the license box is still greyed out. It’s not possible to type anything in the box or press any button other than run compatibility test.
Did you see the depth map after you clicked “Compatibility Test”? If yes and if the test was completed successfully, just close the activation tool and run it again. You should see the active field for entering the license key.
If you didn’t see the depth map, please run nuitrack_sample and provide us with the console output.