Baseline (Widescreen) Solution & Issues
The monitor's native resolution is used by default. All common widescreen resolutions are listed in-game. 1280x768 is not listed but can be used by manually editing sw.cfg in C:\sw3dg\EvochronMercenary
FMV videos stretch from 16:9 so are skewed at any other aspect ratio; everything else has the correct aspect ratio at all tested resolutions (including 1280x768) with the partial exception of loading screens, which stretch from 4:3 when using 16:10 resolutions (whereas 16:9 and 15:9 have the correct perspective), but this has no effect on gameplay since the loading screens are non-interactive.
Ultra/Super-Wide (21:9/32:9) Specific Solution & Issues
Eyefinity / Surround Specific Solution & Issues
4k UHD Specific Solution & Issues