Is it possible to install the AnalogXSimpleServer on a NAS? Or can it only work on a (Windows) PC?
As far as I know, NAS devices have their own operating system and interface. Unless the SimpleServer hasn't been especially developed for your NAS, then it won't run. However, I would check the add-ons and packages for your NAS because there should be a HTTP server ready to be installed.
According to the official website, the software is known to work on all Windows operating systems.