Baseline (Widescreen) Solution & Issues
This game DOES support widescreen resolutions, but not via the game launcher. Only 4:3 resolutions are selectable using the launcher.
However, widescreen resolutions can be used by editing OPTIONS.TXT as follows:
1) Open c:/program files/ShadowGrounds/config/OPTIONS.TXT using Notepad
2) Scroll down to "screen_height =" and "screen_width =" and insert the resolution you wish to use. (eg. screen_height = 1050 and screen_width = 1680)
3) Save, then run the game. Easy!
Ultra/Super-Wide (21:9/32:9) Specific Solution & Issues
1) Open options.txt in ...\Steam\steamapps\common\Shadowgrounds\Config
2) Scroll down to "screen_height =" and "screen_width =" and insert the resolution you wish to use. (eg. screen_height = 1440 and screen_width = 3440)
Eyefinity / Surround Specific Solution & Issues
Same as WS solution above.
4k UHD Specific Solution & Issues