Vegas 13 pro - I had used up trial version and bought full version from Amazon. Installed ok but on activation it said 'Your Vegas Pro Trial has Expired' I entered serial number and it said it would close application and restart. On restart the same message comes up (Your Vegas Pro Trial has Expired) and the process cycles without result. I have tried re-installing all and work-rounds etc. to no avail. Please advise urgently fix, or will have to return as unfit for purpose.