bapu
Jesse,
Did you remove 4.0 first? I did not. I don't recall what I did from 3 to 4.
No bapu,
I had RG 3 and purchased RG 4 and I was given RG V for free when it was made available.
I installed RG 3 over RG 4 without problems.
When i was sent my email to download my RG V, I just ran the installer and it updated over RG 4. When I went into Sonar Platinum and looked at the project that had RG 4 as an instrument, it was now RG V.
I also got two desktop icons, one for RG V and one for RG Steel Strings or whatever it was called. (Nice).