Hommelwomb: @3leminator
You also have to swap out the audio.dll file.
As you are German, you could go to
https://deutschpatch.de/ and download "Battle Isle Incubation + Wilderness Missionen" to update your English version from GOG to German. It already includes working dll files.
Thanks for the hint. I checked/repaired my installation (with the gog galaxy function), got the "deutsch-patch" and replaced the sound.dll and the audio.dll with the one in the "Windows Fix" directory of the Incubation.zip. The behavior is the same as when i replaced the two files before (yes, i already replaced the audio.dll) -> the screen flashes for a moment and thats it. in the running processes one can see incubation.exe for a second and then it disapears. I also tried to switch to 3Dfx with the Settings.exe, but when i click save and lunch nothing happens, only the settings-dialog disapears.
At last i copied the other files of the Incubation.zip to the installation directory of incubation but that doesn't change anything
UPDATE:
Out of curiosity i tried to start incubation yesterday one more time and some how it starts and is running since then fine. The only problem i have is, that i have no sound in the videos. I have no idea, why it is running now, only thing possible as far as i can tell is, that a windows-/pc-restart changed something.