AIC HD wierdness re 24fps in a 29.97 timeline - FCP 5.1.4

1) Why would an AIC (Apple Intermediate Codec) HD file not play properly on another G5 with a Kona Card yet play perfectly on my G5 (no card)?

2) In FCP 5 how is a 24 fps file handled in a 29.97 timeline?


We have an HDV FCP project that was mastered to a D5. When I just updated some titles, I was surprised to see that the original titles were 24 fps even though it's a 29.97 HDV timeline. To keep everything the same I did the new titles with After Effects at 24 fps also.
I placed the new titles into our 29.97 timeline to tweak the fades and then made a 29.97 QuickTime movie using the AIC codec (small enough to load up to my server) from the new FCP timeline secton.

PROBLEM: The post house could not get my AIC files to play smoothly on their Mac with a Kona card. They would stutter and freeze.
I've checked again and they stil play fine on my G5 Dual 2G (no Kona or Black Magic card).
The obvious difference is that my timeline is in HDV and theirs for the insert is a Kona HD variety but the AIC needed to be rendered (perhaps the proper word is conformed) either way.

We did a work around using my animation work files and their analogue HD edit bay, but
I really want to understand what occurred here for my education.
Thanks