Is anyone else having the problem of the 64bit version of 12 crashing on exit?

Any more details? Windows 7 or 8? IE 11? What happens if you install Windows 7 SP1 on a new VM. Does it work then?

More than often, OS thinks application has crashed if it performs anything for more than 5seconds. In such cases OS shows corresponding window asking to kill application. Do never agree. Just close this "good suggestion" using its [x] button and wait a bit longer. PhpED shutdown may take significant time if your project is large. You can greatly reduce this time if you remove or hide all project directories that contain unneeded files such as copies, backups, minified versions of files, old/different versions of the same libraries etc.
If you encouter a real crash and that window shows "APP CRASH" instead of "APP HANG" in the details, please contact support.