I'm experiencing a little bit of brain damage getting accustomed to Magix Software as producers of Vegas vs Sony. And it's not as if I'm overly nostalgic for Sony; I feel pretty confident that Magix will be a capable steward of the franchise. But when it comes to some of the technical details, the transition is proving tough for me. Latest example: I have been a paying customer since Vegas 8, including several upgrades, and I recently upgraded to Pro 15, which went smoothly. But I had to repair the operating system on my Vegas machine, which caused me to have to reinstall Vegas from the Magix download site. To activate the software, I'm being asked for a numeric serial number, but all I can seem to find are alphanumeric product keys from my various past downloads. It's just a casualty of the change in systems, but I'm not sure how to remedy this.