When you say not starting there is no running window just an icon on the task bar at the top with roon logo there…you can click this to activate launch at startup too
As @wizardofoz mentioned, Roon Bridge starts up as a minimized process in the system tray. I just want to clarify here, you do not intend to use the Mac OS to browse your Core’s library at all and just use it as an audio output device?
If you wish to be able to browse your library and perform track selection you will need to install the “All-in-one” version of Roon on the PC and then connect to the QNAP as a Core. These instructions highlight this kind of setup.
If you only wish to have Roon access audio devices connected to the Mac OS (such as a DAC connected via USB to the Mac) then Roon Bridge would would be sufficient, but as I mentioned before do keep in mind that Roon Bridge has no interface so you would need to configure and control the Mac’s audio devices from another Roon Remote.
Please let me know which kind of configuration option you are trying to use and we can take a closer look at what could be going on here.