The other day I fired up an instance of Z3TA+2 in Logic (My OS is Snow Leopard 10.6.8) and was greeted with a high pitch squealing noise that nearly made me go deaf. I found this odd, as my product is legit and was working fine. After contacting Cakewalk, I was informed that there is a serious bug that prevents the plugin from displaying a secondary registration window upon its first initiating in your DAW. To prevent others from experiencing this nonsense, here's the solution Cakewalk provided me: 1. Delete the following files: Macintosh HD\Library\Audio\Plug-ins\Components\z3ta2.component (or similarly named) Macintosh HD\Library\Audio\Plug-ins\VST3\z3ta2.vst3 Macintosh HD\Users\”UserName”\Documents\Z3TA2 2. Delete the following plist files located at User\Library\Preferences\ByHost tts.plist com.cakewalk.z3ta2 3. Download a fresh installer from your Cakewalk Account Page. 4. Install and insert serial number when prompted during the setup. 5. Open your DAW and initiate Z3TA+2. The reg window should now appear, and you can insert your registration number. Hopefully this will help anyone who has experienced this yet. And if you haven't, be prepared to be blasted with a deafening tone after 30 days if you downloaded the original Z3TA+2 installer package. How they managed to not come across this "little" bug whilst Beta testing is beyond my comprehension. Cheers.