FLStudio 20 to work fine on it's own. I can get Ableton Live 9 to work on it's own. I've been using Rewire between FLStudio and Ableton in previous versions (Windows XP, Win7) for many ...
FLStudio simply goes to 100% CPU load and freezes once it's done loading, I can't do anything on the project (or on my computer for that matter.)
I'm running a fair bit of VSTs in the project ...