Hi. Sorry if this is a dumb question…
I tried the Vray 5 demo and installed it with Max 2021 and signed in with my Chaos account and it let me run the software etc.
I have now purchased Vray 5.1 and an extra Render Node. I can see in the licence Web browser - that when running Vray - the newly bought version is active - not the demo:
So - I assume I don’t have to do anything or re-install anything as it looks like its all working and has just ‘ticked’ over to using the full licence?
Or am I wrong?
Thanks.
Yes, that is correct you don’t need to reinstall V-Ray. Once the trial expires, the full license will be engaged.
Feel free to reach us if you need any help 
Super - thanks Borislav