Looking for the Insteon binding maintainer - I have questions!

In the documentation for the binding in the Adding New Device Types section, it says

You can however load your own device_types.xml by referencing it in the network config parameters:

but I don’t see where the network config parameters are specified. Is it in a file or accessed via the UI? Both? Either? How?
I tried adding my own file, /usr/local/openhab/insteon/ezrain_device.xml, and adding it to the code of the hub so it looks like this:

UID: insteon:network:local
label: Insteon PLM or Hub
thingTypeUID: insteon:network
configuration:
additionalDevices: /usr/local/openhab/insteon/ezrain_device.xml
port: /hub2/Hexham24:bHNxxRo4@192.168.2.20:25105
devicePollIntervalSeconds: 1000
location: Office
but nothing changed. It still doesn’t know about the productId I created.

Do you see anything in the openhab.log file? You might need to enable debug logging to figure out what is going on. The source code for loading the additional devices file is here.

The current devices are defined in here.

The current features are defined at here.