Slitherine

Are patches automatically installed by slitherine ? Does the user have to do anything like downloading the patch or what?

If you bought at the very store of Slitherine (or Matrix?), you may have a link if the patch is adverted by the news on Slitherine website.
If not, you have to DL the patch in your user library: you log on My page / My games, and go to your game page, then sure you apply it, launching the patch exe.