[Chris Ransdell]“It is rendered to a thunderbolt Gdrive.”
Have you tested read/write speeds of this drive? Uncompressed stuff will eat up bandwidth really fast, especially if you make multiple tracks going on.
In the replace footage dialog box make sure that the image sequence box isn’t ticked. AE recognizes image sequences automatically and will offer that option by default.
I don’t know how the footage looks, but according to that screenshot I’d guess that there’s too much movement going on for the stabilizer settings you’ve chosen.