I have a Win7 laptop and ran the install on it. The install asks where the 32 and 64 bit versions of the vst are to go. 64 bit went to local VST drive, 32 bit went to mapped VST drive on my XP32 DAW.
I already have some NI VSTs so Service Center was already on my DAW. Opened Reaper on the DAW, the VST was available so I added it to a track. The GUI opened and I selected activate and it did.
Then went back to my Win7 laptop, opened Reaper64 and did the same thing.
It did ask to enter the license string from the downoad link email, but once I did that, it activated so I now have the VST on both my computers, XP32 and WIN764.