"Repel" simulation not displaying correctly in FCP

(Using FCS 3.) I either discovered a bug or, far more likely, am missing something obvious. I have a fairly basic Motion project - 5 pictures, slowly being repelled away from the center using the "Repel" simulation. Looks great in Motion. However, when I bring it into Final Cut (the motion file directly), it displays wrong. Images are in the wrong spot, they animate in the wrong direction, and it moves much slower than what should be happening. This occurs even after rendering in Final Cut.

I haven't seen this issue before, though this is the first time I've used "Repel". Tried on a different machine too and had the exact same outcome. The images I'm using are vector PDFs. I also tried with some jpgs thrown together, and that time repel didn't display at all.

I know I can just render out to a Quicktime, but I feel like I shouldn't have to! Is this a known issue, or if not, anyone have any suggestions? Thanks so much!