Actually both, install it as server and client on Win 10 Machine. The Release Notes for 6.3.0.168 does not mention the support on Win10 but it actually runs. The only thing is the installation will not complete in my system. I am not sure if there are local policies preventing to complete the installation. The processing install bar will show 100% and "cleaning up temporary install files" message will be shown forever.
Workaround, once you kill the launcher from the Task Manager everything looks "fine", I can discover my devices, Map it, open flexviews from the console, etc.
Unfortunately I can not upgrade the system because this is tie-up to a control system and the "qualification" takes a lot of effort.
Now I am looking for some document that actually says it is supported and find the root cause of the incomplete installation.