My next step is to try Daz 4 in Linux. I'm running Linux Mint right now and I'm going to install Wine (the Microsoft compatibility layer) here in a bit. There are some good results in their app. database but those are for Linux versions from last year (the one I'm running is from this year) and nobody has apparently tested Daz 4. So, it should be interesting.
If it doesn't work, I'll try Windows again but put the files in C:/Program Files instead of where it wants to go, C:/Program Files (x86). I never thought of doing that until you mentioned it.