The Game offers only 4:3 resolutions - you need dgvoodoo (for higher resolutions) and a hex editor to get it HOR+
Download the newest version of dgvoodoo and copy the 3 DLL Files from MS Folder to the game root DIR.
Hex edit resolution: Go to -> ...\Steam\steamapps\common\ZanZarah\System\zanthp.exe
Look for 20 03 00 00 58 02 (800x600) and change all values to 00 0A 00 00 A0 05 (2560x1440) - see here for other resolutions.
Now go to --> ...\Steam\steamapps\common\ZanZarah\ZanZarah.bat
and add -console after start zanzarah.exe --> start zanzarah.exe -console
Now start the Game and choose your resolution from the startup menu / Video Options.
In game press F11 and write for 16:10: fov 1200,750 and for 16:9: fov 1350,750
------------------------------------------
Optional higher refresh rate:
Go to --> ...\Steam\steamapps\common\ZanZarah\ZanZarah.bat
and add -windwed after start zanzarah.exe --> start zanzarah.exe -console -windowed. Use Borderless Gaming for fullscreen.
Combined with reshade (DX11) it runs and looks quite good.