I'm having the same problem. I've installed this before (few weeks ago) and it's just worked straight away using the SMB network. I've had some problem with TVheadend and decided that I'd just start again. Regretting that now!
What are you meant to put in the 'add network location' box? e.g., I know the IP of my NAS ***.***.*.** do I add the :5000 I have to put on to access the admin screen from my browser; e.g., 123.456.7.89:5000 (is this the sever name... or is it the name I've given my NAS; e.g., MY_NAS? Should it be SMB in protocol?
I've done all the actions above and the changing of SMB1 to be min and max has resulted in me being able to see my NAS, but it doesn't let me connect, I just get the 'operation not permitted'... can anybody help out there please?