When I create titles in X, there's an issue on playback.

The last half of the dropping title appears stuck at the end.
Believe this is an issue with the auto render function.

To recreate issue:

Create New Title.
Select a style (I chose continuous under build-in)
Copy and Paste title (I had a gradient set as bkg)
Upon playback, the end of the title will be stuck

Workaround:
I simply found retyping the title fixed the issue because it caused FCPX to re-render.
Also, adding a space at the end fixes the issue.

If I was allowed to post attachments, I would show you...
Hope this helps someone else.

_CD