Transport Giant works fine on 2k (e.g. 2560x1440), or 4k (e.g. 3840x2160) screen resolutions. The problem is that DirectX 7 doesn't support resolutions higher than 2048, however there are patches that remove this restriction.
Option 1: Using a very simple LegacyD3DResolutionHack program from:
https://github.com/UCyborg/LegacyD3DResolutionHack/releases/tag/v1.0.0 For this one, simply unpack DLL files (d3dim.dll and d3dim700.dll) from the .zip archive to your game folder.
Option 2: For more advanced improvements, you can use dgVoodoo2 instead:
https://dege.freeweb.hu/dgVoodoo2/dgVoodoo2/
For this one, unpack: dgVoodooCpl.exe, dgVoodoo.conf and MS\x86\DDraw.dll from the .zip archive to your game folder. I recommend to play with some settings as there are nice improvements such as windowed mode or other graphical improvements.
Steps that need to be done every time: The screen resolution can be changed by editing file
config\GameStatus.xml For example:
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<DisplaySettings ScreenHeight="2560"/>
<DisplaySettings ScreenWidth="1440"/>
[/code]
After that, your game will start with the correct resolution, but you won't see it on the list in the game settings. Also whenever you change graphics settings the resolution will be lost and you'll need to quit the game and edit GameStatus.xml again.
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