When I used it as a trial I had no problems, since purchasing it, it keeps locking up and not responding, Why??? Very frustrating...
When you purchased it, did you convert your trial version by inserting the serial number and activating the product or did you, not knowingly, re-installed everything all over again?
To convert from trial version to the full version is just a matter of entering the serial number and everything should work as normal.
Did you make any changes to your system? I am assuming here that you are using a Windows System.