Usually you build at least two. One will be space qualified and the other sits in a lab. Any changes you make to the flight software are tested on the lab version first to prevent expensive/embarrassing mistakes.

I ask for a several reasons because I had a similar idea in the past.

What range does it work over? Tradition MoCap has a pretty good range/accuracy. How well does your 1mm accuracy stand up over say a 15m distance?

Do you have it working with say, 30 RFIDs and maintain an accuracy of 1mm ?

One of the nice things is that it doesn't have to be line of sight, how well does it work with waves travelling through clothing or other objects etc. ?

Are you operating in 1 frequency range? How do you deal with noise?

What sort of resolution can you detectors operate at?

I basically concluded to get it working reliably. Effectively at high resolution (I move my hand real fast, how many samples was that?) and accurately (using several frequencies) would cost quite a bit, be complex to write the software for and be a real pain to deploy. Several of these issues can be fixed by using active RFIDs but again pushes the cost up. But either way, good luck with it :)

You mean like the SIM's ? I lost track of the number of expansions they made.

'US Copyright Office' -> Move your servers to a place that is outside of US jurisdictional where the copyright laws are not controlled by large media companies. Last time I checked US law does not effect the rest of the world.