@uveso I figured out a workaround that might only be required because I had another issue I had forgotten about.

I set all my monitors to Landscape and then enabled the NVidia Surround. While everything was in Landscape, I was still able to start the game and then change resolution settings to windowed (game wouldn't accept windowed or resolution launch options for some reason, through steam or FAF or .exe shortcuts). After it was windowed mode, I was able to rotate my display back to profile and the game continued running.

To be extra specific, Windows 10 monitor Display settings still say Landscape and Nvidia Control panel rotation says Portrait. So fooling Windows 10 might be a component of this.

I had a Direct3d issue where the game wouldn't start and tried everything under the sun to fix it. Clean reinstall of latest video drivers, C++ libraries from 2005-Current, re-install DX9, reinstall game, mess with launch options, compatibility options, direct play, preset resolution, windowed mode, etc, etc, etc.

If it showed up on google, I tried it. If it was mentioned in this forum, I tried it. Nothing worked.

In the end, it turned out the problem was that my monitor being in Portrait orientation was the problem. Apparently the game only accepts Landscape orientation.

This is a problem, as I have a multi-monitor setup with only vertical monitors. Typically used in conjuction with Nvidia Surround, to make it function as one giant monitor. But the game still treats this single virtual display as not being in Landscape, despite it being virtual and wider than it is tall.

If anyone has any idea how to solve this without me having to buy an even bigger monitor stand so that I can physically rotate them to a Landscape orientation, I am all ears. >.>