Color Finesse will work with any format of video that After Effects or FCP can read.
For your application, I'd recommend bringing your DV footage into a 16-bit After Effects project, color correcting with Color Finesse, then rendering out of AE into whatever format you intend to deliver your stock footage. Most of the CD/DVD-ROM based stock footage seems to use JPEG at 90-95% quality.
Despite starting with compressed, 8-bit, 4:1:1 DV footage, you want to do your correction in as large a color space as possible. You can then deliver in the format you choose. The quality of this will be superior to doing all your correction in an 8-bit environment, such as FCP. Even if you choose DV as your final format (which I wouldn't recommend), the results of having a deeper intermediate stage will be visible.
Bob Currier
Synthetic Aperture