I just tried it on a older computer with OSX 10.10 and I am still getting the error so it seems I am doing something wrong. Shall check during the day again .
EDIT: I was doing the wrong line in the terminal :-)
ninjamsrv mysetup.cfg is the correct .
Now it starts but there is an error in reading the .cfg file "error loading"
Anyways I am getting there :-)
EDIT2 : The compiled version is back online for download :-)
https://cockos.com/ninjam/
but I still have the "[config] error opening configfile 'example.cfg'" error