I’m not sure what FCP is doing that is causing the color shift, but here is a way that seems to avoid it:
* Give your AE artist your raw media, that way nothing gets changed via an Export from FCP. I used our Pro Import AE plug-in to get my shot into AE.
* As you know, your artist cannot render directly back to HDV from AE, so he/she renders to the Animation Codec.
* As you know, FCP shifts the color of the Animation Codec movie when you drop it back into your HDV timeline, so DON’T import the Animation Codec movie. Open the Animation Codec movie in QuickTime Player (Pro) and Export the movie to HDV.
* Import this HDV movie into FCP, it plays in real-time and doesn’t have the color shift.
— Wes Plate
Automatic Duck