I always get the same errors when trying to use inverse telecine to recreate 24fps film rate from 30fps captures. It will say that the "top field first" option is wrong and I should try the opposite setting. Except the opposite setting results in the same message! There are only two settings, after all. On the extremely rare occasion I don't get that message, JES quits soon after and doesn't produce any usable files. Maybe this works fine for simple deinterlacing, but I just can't recommend it for inverse telecine. However, if I only needed simple deinterlacing, I would use something like ffmpegX. That has a deinterlace option and would let me encode to Xvid or h.264 in the same pass, so there's no additional loss from later re-encoding. As of right now, I have to sadly say that there's still no inverse telecine solution for the Mac, which is a damn shame for a platform that's supposed to be so video-friendly.