Hi Jack,

Try the gamma at what looks good in your project (I warned you it will look horrible on the computer screen). I think the general idea is that you could further color correct in FCP so long as you have the information in the pixels from Carrara. Since this is a one-man project, get it as close as you can (but if you need to err, go on the bright side). Not everyone sees the same, and dark or low contrast images are usually the hardest to see.
if you are controlling the presentation (they will see it on your TV) then you have no worries, but if you need to plan for lots of tvs and won't be controlling the end environment, go just a little brighter (I mean higher gamma) than you are comfortable..., especially if there's a chance it wll be seen on a video projector.

good luck!
holly