Sorry to hear you are having problems getting the newer Lumion version running on your system.
Presume its v3.1 Free you are referring to.
The rest of the system specs looks good.
"Am I failing the benchmark? - Yes, that is what is happening
Do i need to uninstall 2.5 or something? - No.
Is it a licensing issue? - No (not that I can think of at this time)
I have a user name tied to 2.5 free. None for 3.1 - Not required now
Maybe graphics card failed benchmark? - Yes, looks like insufficient GPU power as its not getting right through the test
First off, you can run both v2.5 Free and V3 without v2.5 affecting v3. They install and operate independently including the licensing system now with v3, so no need to de-activate 2.5 Free as such.
So, V2.5 is in now way affecting the running and getting stuck in the Benchmarking of v3.1.
V3 definitely does require more from the GPU. The minimum passmark level (refer LUMION 3: Minimum hardware requirements
) now sets it to 1500 and your Quadro is 1928. So there's a bit of leeway there for you and you should still be able to run, just not more complex scenes. So its a little difficult to think what else might be causing your problem.
Even though you were able to run v2.5 fine, there have been a lot of changes under the engine for v3 to provide some of the added high-end features of v3.
There are a few others with Quadro cards running v3, but the benchmark scores so far are some of the lowest recorded. Also, no two cards are the same and yours may not be quite suitable for Lumion (OK for your CAD of course).
It could (for the money and time etc) be well worthwhile considering investing in a powerful gaming based GPU of either NVIDIA or AMD/ATI. As you have noted, Quadros are of course not directly supported, rather the GTX/Radeon range as those are what the development of Lumion target and directly support.
Note: the new Benchmark in the new update of v3.1.1 just released (6/04/2013) is even more demanding.
Couple of things to try:
1. Did you try re-starting Windows with no other applications running so that Lumion is the only one running?
2. Have you got the most recent WHQL drivers for the Quadro card from NVIDIA?
Thank you for your detailed feedback, the detail and time is much appreciated.