On-premise openwrt firmware-selector clarifications

Hello. I'm new here so sorry for silly questions.

I've a NanoPI board family, and I want to have an hosted firmware-selector/asu from where I can build custom image for this board only.
I've asu up and running, and cloned the firmware-selector project.
The asu is running on armv8 server, so it's a native build environment.

Now I'm suck at the stage of using misc/collect.py script to download only rockchip/armv8 and only openwrt > 23.0x versions.

To be honest, I've not understood how to do that even reading the documentation.
I'm sure that it's my fault..

The script, according to the doc, "update the www/config.json" file.
There is no config.json, but config.js.
Which I suppose is the same.

In that file, I read in regards of versions: // Path to were overview.json can be found with a list of openwrt versions.

What is this overview.json? Where is located? For what is used for?

I've updated the asu_url with the address of my asu server, and set the default_version to 23.05.2

The image_url is the default one, just decommented.
The info_url, is not clear to me what is used for, is at the default setting.

I ran: ./misc/collect.py https://downloads.openwrt.org www/ as stated in the documentation...and i got the www/data dir full of openwrt version/device files, as expected.

I can set variables, according with the documentation, but I don't know how to set them ({version}, {id} etc). Are they putted in config.js/json file? Are env variables?

Can you please point me to a documentation that explain what I would like to do?
Or clarify the above-mentioned points?

Thank you very much if you took the time to read this far :slight_smile: