I had a problem like this too - but then I'm running Reaper 2.3 something so I'm a bit behind. As a workaround, you may want to try something like 'savihost' (it's free I believe, google it) which is designed to run a vsti without using your actual daw. Savihost might allow you to at least get your auth code in and then you'll be fine in Reaper. (In my case I have Acid Music Studio 7 so I used that to authorize.)