So, I was right, 7.5 is a completely separate and independent application. I still have 7.0.6 on my drive and I can use it. Actually I still even have 6.5.
I like this approach. Anything wrong with 7.5 and I can still go back to 7.0.6.
I had to re-insert all the links to my own VST 2.x folders though. Same with the preferences. All gone. I could copy them from the 7.0.6 folder, but something tells me I shouldn’t do that…