Here is detailed information on how to add your Toontrack product as a plug-in in Logic Pro.
This guide was made using Logic Pro version 10.7.4.
If you do not already have a track that you want to add a virtual instrument to, right-click the track area (marked in red in the picture below) and select “New Software Instrument Track”.
Select the track you want to add the plug-in to and make sure that the “Mixer” button located at the top left of Logic is activated:
Go to the Mixer at the bottom of Logic, select the channel that you want to add the plug-in to, and click the arrows to the right of the current software instrument in the Input box:
Go to AU Instrument > Toontrack to find your installed Toontrack plug-ins. Select your desired plug-in.
Click on the arrows to the right in the Audio FX box in the mixer for the channel you want to add an effects plug-in to. Navigate to the Audio Units > Toontrack folder and select your installed Toontrack effect plug-in (like EZmix).