V4 --> v5 ? v4 + v5?

Hi, I googled for a document or discussion re upgrading from version 4 to version 5 but didn’t find any. Did I miss something?
Is there anything on retaining version 4 capability along with version 5?

I downloaded version 5 from juce.com When I ran Projucer, I was a bit dismayed to see that it opened my version 4 project. I exitted it, and it seems none of my files were modified (whew!). However in trying to clone my version 4 project, and upgrade the clone to version 5, it now seems the V5 and V4 Projucers maybe clashing in the registry. I’m on Window 7.

Thanks for any input or comments.