All 3 default cities work free without license:
Broxburn, GB — 18°C, overcast clouds
Holambra, BR — 24°C, few clouds
Ryjewo, PL — 20°C, overcast clouds
MacOS
Install to /Applications:
% cp -R WeatherWidget-0.0.7.app /Applications/
or
copy and paste WeatherWidget-0.0.7.app into Applications folder