NSLog

In the app settings, there is an option to enable NSLog so that all tracing can be found with cfgutil

When enabled, all logging can be viewed on a Mac:

• install Apple Configurator 2 on a Mac (it's not necessary to run the application)
• Open a Terminal session (on Mac click Search button top right, type 'Terminal', double click on the Terminal app)
• change directory to Downloads folder , type :
  cd Downloads
• copy paste this :
  /Applications/Apple\ Configurator\ 2.app/Contents/MacOS/cfgutil syslog | grep xDrip-NSLog > xdriplog.txt and press enter

Now use the app, all logging information can be found in the file xdriplog.txt
You can also leave out the redirection to file.

You can now send the file to anyone else who wants to give support.

Or to view the contents in real time while testing

• open a second terminal session (or the same as the first if you don't need the output in a file)
• type:
  /Applications/Apple\ Configurator\ 2.app/Contents/MacOS/cfgutil syslog | awk '{split($0, a,"xDrip-NSLog ") ; if (length(a) > 1) print a[2] }'