I noticed that ratings for files input on the client are not sent/updated to the server. Is this another limitation or is something else wrong with my setup?
there is a setting under network that says "automatically sync changes made on client back to server on shutdown". What is this for then?
Ratings absolutely sync back to the server version. I do it every day from work.
I rate a few dozen songs throughout the work day. At the end of the day, I simply choose File > Close.
The MC main window closed, and then I get an info box showing that it's checking for changes.
That closes a little while later.
When I get home, those albums I rated at work are all correctly marked with stars.
Make sure you run exactly the same build of MC at both ends. I'm using version 15, build 115.
I have this setting checked: "automatically sync changes made on client back to server on shutdown".
Perhaps you could uncheck it on yours, close MC, restart MC, then check that option again.