you may need this pasted in at the end of the file as well for it to work cant remember i did it a while ago
“driver_null” : {
“enable”: true,
“id”: “Null Driver”,
“serialNumber”: “Null 4711”,
“modelNumber”: “Null Model Number”,
“windowX”: 100,
“windowY”: 100,
“windowWidth”: 1920,
“windowHeight”: 1080,
“renderWidth”: 1344,
“renderHeight”: 1512,
“secondsFromVsyncToPhotons”: 0.1,
“displayFrequency”: 90
},