Not sure what the problem is.......You should be OK of your 32MB video is true/not shared video. Also 384MB ram is what I have and G2 runs very smoothly for me on a 1M MB P3 with a separate 32MB GeForce vid Card.

Without reading about it at the Real FLight website I would tend to doubt that you could add the add-on files......cuz that is why it is "Lite", just a barebones sim for those who want to save money on the initial purcase.