When you press play, are you playing back the regions that you have captured in VocAlign Project 5, or are you playing back audio elsewhere along your Logic Pro timeline?
(The timeline is the length of your Logic Pro Tracks window, where your regions are placed to be played back.)
Only the regions captured in VocAlign Project 5 will play back - other audio on the same track will not pass through.
Do you get normal playback when you bypass the VocAlign Project 5 plugin on that track?
If you do, please see this article: Loss of VocAlign audio output - why do tracks become muted in Logic Pro?
Remember:You can always access the VocAlign Project 5 User Guide instantly by clicking the ? button in the top right hand corner of the plugin window.