VX-5R - Supported FT-857D - Supported FT-897D - Not Supported
Yes it is. The 857 and 897 are functionally equivalent and the single driver works for the both of them.
FT-8800R - Supported FT-7900R - Not Directly Supported (Programs as an FT-7800R)
The 7800 and 7900 are the _same_ radio. They even identify themselves as the same exact model. CHIRP couldn't tell the difference between them if it wanted to.
FT-2800M - Supported TS-2000(x) - Not Supported
Tom has a prototype driver for this and has been looking for people to help test.
http://chirp.danplanet.com/issues/217
KG-UV6X - Not Supported
Yes, it is.
I'm not sure where you're getting your information, but the front page of the chirp website is where we keep the definitive list of supported radio models.