SOAP UI Pro Trial - License key rejected

Hi - tried to put this post in support forum but seem to be unable to post there.

I am trying to trial SOAP UI Pro - but license key is rejected. I am browsing to the .key file sent in the email.

I am running Windows 8 within a VM on my Mac. I have SOAP open source installed also.

Anyone have any similar experience or a workaround? I have tried a no of things (re-downloading key, unzipping it in another app etc). Nothing works.

thanks
Daniel