AMD are behind the Radeon graphics cards though, which is why I linked their site . Also, their update software doesn’t always like keeping the graphics card drivers fully up to date, so if you use a Radeon you may want to check anyway .
Anyway, assuming it’s not that for the moment… hmm. Some info on your version of Stonehearth (see bottom left corner of the main menu, be sure to include the revision/build number too - latest is 1658) & Windows, CPU, RAM and graphics card may offer some clues, although the fact that it could run before is puzzling. Have you tried a clean install (ie, making sure the folder below is deleted)?
Obviously Steam may not be installed in C:\Program Files, but the rest of the directory structure is accurate for Stonehearth. Anyway, if you uninstall Stonehearth, delete the Stonehearth folder in your SteamApps\common folder, and re-install using the latest update (right-click Stonehearth in Steam, go to Properties, then Betas, then choose the latest option), does that help at all?
Edit: I know you’re using the unstable / latest version already, just want to make absolutely positive that it’s installed cleanly after a full uninstall .