Honestly, the hammering piano at the beginning is the weakest part. It really doesn't scream "Epic Comeback" to me, unless this happens to be your epic comeback in which case I can't really say anything to dismiss it since it's meant to be you or something.
Oh by the way, your computer may have been "buggy" because your hardware was insufficient for exporting your audio. It's most likely your processor. You may want to check if you have hyperthreading on.
If you're using Windows, use System Config; Boot; Advanced Options & increase the number of virtual cores you're using. Your computer will need to reboot to make the change.
If you're already hyperthreading at max, you may want to uninstall FL Studio, get CCleaner to clear the registry of FL Studio files & reinstall it.
If neither of those things work, you may need to scan for viruses. Get Malwarebytes & Avast if you don't already have them. Run a custom scan in Malwarebytes & checkmark every option. If you discover an infection you have two choices:
#1: Scrub the hard drive clean by reinstalling Windows.
#2: Go here: http://www.techspot.com/community/forums/virus-and-malware-removal.28/ & follow their instructions on how to disinfect.
If you have no infections & you have few virtual cores, it might be time to upgrade your processor.
~Review Request Club.