Hi,
I am still working with my perpetual 3.7 version. I think of getting a new anual lic for vray 5. Will it be possible then to use v5 with max 2020 and a version of next with max 2018 to finish some projects and to collaborate with others?
Yes, V-Ray Next will work fine with your V-Ray 5 license.
Best regards,
Vlado