Baseline (Widescreen) Solution & Issues
The game normally runs at 800x600; higher resolutions can be set by editing autoexec.cfg in the installation folder and setting ScreenWidth and ScreenHeight accordingly but this causes interface issues.
Using any resolution other than 800x600 results in messed up menus (see menu screenshots section). Some only have some items displaced while others, such as the inventory screen, are totally unusable. This even applies to other 4:3 resolutions such as 1024x768.
Ultra/Super-Wide (21:9/32:9) Specific Solution & Issues
Eyefinity / Surround Specific Solution & Issues
4k UHD Specific Solution & Issues