Slitherine

There doesn't seem to be a section on this in the manual.
Where should you save scenarios you have created so that the game recognizes their existence?

Next to your saved games, you have to make a new folder.
Home > Documents > My Games > Panzer Corps 2 > Scenarios

For campaigns:
Home > Documents > My Games > Panzer Corps 2 > Campaigns
I think there may be an issue with campaigns but have not heard back from Devs yet.

Thank you 'dalfrede' for this nugget.