I installed X2 over a clean Windows 7 install. All went well. Didn't bother re-installing X1.
Then I decided I would like to have Guitar Rig 4 LE back again as I missed it, so I did a selective install of X1, just specifying GR4.
The install completed and I was able to run GR4 and register it through the NI Service Center. It loads both as a VST and standalone.
However, there are NO components or presets - just an empty browser window. It's driving me nuts, can't find them anywhere.
What have I missed?

Had same problem. Go to Native Instruments website and download the latest Guitar Rig update. When I got the update all the presets showed up.

Brilliant. Thanks for that. Will try it when I get home.

That fixed it. Thanks for tip.