Unfortunately, I don't know of a step by step process. There probably isn't one because every person's situation will be different. My settings will be different from yours. What specifically is the problem? I am going to guess the JSON file?
Need more info. Which SDR(s)? What are you trying to monitor? Just in case, which RPi and software?
I know it is a pain in the butt as I have spent countless hours and considered quitting but at the same time, I wanted to overcome this as this has potential. I have been been able to finally able to download radio traffic onto the RPi but I am also seeing 8 Kib files in the download section which I think indicates interference and/or not tuned correctly. I am not sure what happens to those files. Are they uploaded? As I type this, I might have a breakthrough on that but still fine tuning.
I am running a RPi 4 and attempting to monitor 8 conventional analog frequencies with 2 SDRs.