First, thanks for looking at getting NOX to run at custom resolutions.
The most interesting resolutions to try and getting Nox to run for me isn't 1920x1080 or 1680x1050. The game crashes above 1024x768 I read, and people might think this is a failure. It isn't so, necessarily. I suggest looking at running NOX at either 840x525 (16:10) or 960x540 (16:9). If you don't know then these two resolutions is exactly half of the native resolutions at these aspects, which means non-blurry scaling, which is important for picture quality.
The advantages in short:
+non-blurry scaling + widescreen resolution
+more of a personal view then you'd get at e.g. 1080p (it's a preference in the end, of course)
+these resolutions isn't gameplay breaking. The game wasn't designed to have a viewing field over 1024x768 which might cause game-play related issues (undetermined)
I'm going to test this out myself later and report back, but I also read that it might not even work in multi-player even if under 1024x768?, so that's a real bummer for me, if true.
Edit:
I have successfully tested 960x540 (16:9) to work in single-player and multi-player !
Note: I've only done very initial testing at this point, but I'll report back with more solid evidence for success and any issues that might arise.
640x480
960x540
1024x576 (This seems to be the maximum stable 16:9 resolution in both single-player and multi-player)
What I did was to only change to the new resolution in both nox.ini and in default.ini. If I only changed to the new res in nox.ini then the game would hang when trying to host a multi-player session. No hex editing is needed for these resolutions to work. The PC gaming wiki should probably be updated to reflex this.