You may encounter the following situation:
Toon Boom Studio requires you to install QuickTime 5 even though you have already installed it.
The problem is caused by the fact that some of the components were unchecked during the installation of QuickTime.
To solve the problem relaunch the QuickTime Player installer and make sure to select Recommended instead of Minimum (we suggest selecting Custom and installing all of the components. The full installation is about 200k more than the recommended one).
Mac OS X (all)