How should Age of Wonders be launched?

Age of Wonders (GoG) is installed and when run a very small window pops up (attached). Nothing else happens. I can close that tiny window but otherwise I have to press stop. Log: https://0x0.st/PrLe.log

Does this have something to do with the fact that the game is intended for Windows 95/98? I think in Windows you usually have to select a compatibility mode.