The colour on the official DVD release is just all over the place. Also a lot of the garbage mattes and other problems are still in the DVD release.
I'm not sure what you guys want to do re the NFR?
I doubt they would give you access to the 35mm masters, more likely a telecined version of the master if that.
If you got the 35mm master - what would you do with it? I'm pretty sure they wouldn't let you take it home and run it through an ultrasonic cleaner and a chemical bath and then scan it a frame at a time. (All 170,000+ frames of it).
Also, every film company that puts a film into the repositry has their own agreement with them re access and so on. So ILM will have a contract with the NFR detailing exactly what is and isn't allowed to happen with it.
What is is interesting is if you can get access to watch the film or to watch a transfer of it, as it is probably a different master to the one on the laserdiscs, and the content may be subtly altered - could be worth a look.