Ah I hoped this system is already clear to all, seems not

.
There is nothing like "active preset". Configuration defined in preset is simply loaded when you tap on "Preset". And this is all ... here all work of "Preset" system ends!! It just overwrite current app settings with settings defined in preset, dot.
So when you later change anything in Locus > settings, it will never be copied back to last used preset. Hope it is more clear now.
@Andrew Heard: Weather in public version is still old good "World Weather Online" service. "Dark Sky" is used only in new version that is available for now only in Beta version.
I can offer to use more services for various regions, but seems for example that your government service does not have any public API for developers.
I started to work on this mainly because
this idea, that I want to do already for many years. Unfortunately pricing of World Weather Online is quite expensive so it was not possible. With Dark Sky, it's no problem anymore.