With todays update we changed the default back from OpenGL to DirectX for Win8 and Win10. UI lag should not be a problem anymore with DirectX.
If the UI is still laggy for you take a look at this: https://steamcommunity.com/app/762650/discussions/0/1709564118771778334/
If your game crashes after this update you can change it back to OpenGL with the instructions on this site: https://steamcommunity.com/app/762650/discussions/0/1709564118769331126/
ea.0.6(37) - July 24, 2018
- Improvement: Bakery produces twice the amount of bread from 1 water and 1 flour
- Improvement: Injured residents now go to the doctor before they go to sleep
- Improvement: Decreased the need for meat and water slightly
- Bugfix: Buildings Pathfinding to prevent stuck (Shack, Saloon, Stonemason)
- Bugfix: Farm animal follows butcher to the doctor/shack/campfire
- Bugfix: Rotation not working in pause mode
- New: 45° Keyboard-Rotation when holding the left Alt key. You also can force this behavior in the controls settings
Full list of patch notes: https://steamcommunity.com/app/762650/discussions/0/1709564118768215114/