Brennan,

Sorry not a quicker answer... This sort of question regularly appears and the answer is to contact Magix Support who are generally very helpful. The activation limits are to discourage illegal copies, but if you have genuinely just been upgrading computers there should be no problem -- they can reset your activation counter. Try here: https://support2.magix.com/customer/index.php

Note: MEP 15 is getting pretty old now and there have been lots of improvements since then. I'd suggest (not an employee, just a satisfied user!) giving serious thought to getting a newer version. Most recommend at least the 'Plus' version with extra features. The 'Premium' version has additional third-part programs included. Try out a free demo version. I don't remember when the project file name changed (from .MVD. to .MVP) but you can continue with old projects using not 'Open', but rather 'Manage Movies' >> 'Import'. 

Regards,

Carl