Transition issues show black background and dont seemlessly connect to the next scene

Thanks Luis. I am not sure if this is what you meant, but please do let me know. This is a zoom in transition (but as mentioned any transition does the same). This is what I mean about it showing a black background instead of seamlessly blurring the 2 together.

Your help is greatly appreciated.

Ah.. that would be unfortunate if so.. but maybe your guess was right. These are paid for 3rd party transitions (An Envato elements subscription) . I did use Dissolve and it worked fine.. but anyone from this pack doesn't seem to work unfortunately. So are there specific transitions for specific video dimensions?

Thank you, I will see if Envato can provide more information on this.

Something slightly different if I may, as you seem rather helpful.. I am also having issues installing titles. In the finder, under movies, it only had a transitions folder by default. Upon researching I saw I could manually create titles, effects, etc folders in this space if they were missing. I downloaded some titles and added it into the title folder (again inside movies on finder), quit FCPX to start again, and none of the titles are showing. Have I done something wrong?

Excellent! Thanks so much. I was adding .localized to the folders inside of titles, not the main titles one itself. I missed it by mistake! Thank you!.