If CamBam asks for the key every time it runs, ensure the CamBamPro.lic file is actually present in the Program Files directory and that you have the necessary administrative permissions for that folder.
If you're in need of a CamBam license key, here are the steps you can take: cambam license key top
It handles 2.5D and 3D profiling, pocketing, drilling, and engraving. If CamBam asks for the key every time