The original author has updated the packages on the Rebble store. You can now just install like a normal watchface and use an OpenWeatherMap API key to activate.
Modified pebble-js-app file for reno pebble watchfaces
Requires a free API key from https://openweathermap.org/
To modify an original PBW file in Windows, edit the pebble-js-app.js and enter your API key. Then, open the file in 7-zip, and drag and drop the new file into the archive.
Location can be changed in the watchface settings and should use the openweathermap location query by city name format.