Thanks a lot for the info my man. I owe you lunch....let me know what your belly wants?

Thanks for this info as I probably would not have been able to find it myself. In case anyone else comes looking later, the above registry edit does work for 4k (3840x2160) on a native 4k screen. I haven't seen any issues so far.

Where do you need to edit? I can't see the info.

Weird that there is a whole comment just nuked out of here. Anyways, I think the values are here:

Computer\HKEY_CURRENT_USER\SOFTWARE\D3Publisher\OmegaLabyrinth Life

Screenmanager Resolution Width_h182942802
Screenmanager Resolution Height_h2627697771

Those are the entries for me. With the usual caveat of only modify your registry if you are confident you have some clue about what you are doing, etc.

Go under properties, general, and under Launch Options paste
-screen-height 1440 -screen-width 2560