Here is an installation guide for Solasta campaigns.
To install a campaign:Exit Solasta if it’s running.
Subscribe to the campaign in the Solasta Steam Workshop.
Restart Solasta.
Click New Adventure, Change Campaign, scroll down and select the campaign.
Choose a party and click start.
UPDATES: when an updated version of the campaign is published and you load a save game, you’ll have the option to load “from disk” or “from save”. Choose “from disk” to get the latest version of the campaign from Steam.
C:\User\%USERNAME%\AppData\LocalLow\Tactical Adventures\Solasta\UserContent\Campaigns
WARNING: do not put this in your Locations folder as you would previously. There’s a new folder called Campaigns.
Installing this way does not auto-update like Steam does so be sure to check back for updates.
To play, see the instructions above.