2560x1080 ultra-widescreen monitor

Windows 8.1

In today's build I can't select ultra-widescreen 21:9 resolutions (e.g. 2560x1080). Only 16:9 ratios are available for me. When I try to select resolution, I end up with 1920x1080 as my highest option. This results in horizontal stretching as opposed to letterboxing. As one can imagine the stretching makes the game look fairly bad.

Manually setting the width in the registry below resolves the problem and is perfectly happy so far after a couple games.

HKCU\Software\MohawkGames\Offworld Trading Company\