What happens if you Share/Computer/AVI?
Also, can you give us a screen-cap of your Timeline, showing the Video Clip and the PiP Still Image?
It would probably be useful to also include the Effects Control Panel open (Edit Effects) with the Effect>Crop twirled open, showing the settings.
With AVI, it works!
I actually fixed the problem by using MS Paint to crop the picture, then re-inserted it into the video.
Thank you for the screen-cap. That looks like it should, unless I have missed something important.
I have done the same, with PiP's, and that is how I do it, with no issues.
Here's one of mine, and it really looks like the setup for your:
The only difference is the version of PrE used.
Glad that you got it sorted out, and that it's now working for you.