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.

Download the campaign zip from mod.io or nexusmods

Extract the zip file to
C:\Users\%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 instructions above.

Prior to Solasta 1.2.9, campaigns were bundled as a collection of individual maps (UserItem). While these still work, the preferred way of publishing is a single campaign file (UserCampaign).

Here's a specific example for installing Vel Explorer:

https://steamhost.cn/steamcommunity_com/sharedfiles/filedetails/?id=2645356635

And here's a starter list of fun campaigns:

https://steamhost.cn/steamcommunity_com/sharedfiles/filedetails/?id=2616379055