While the intro and menus seem to work just fine, the game itself plays like in time-laps. With this ridiculous game speed it becomes unplayable and I can find a way to slow it down.

Is there any fix to run it in normal speed?

I'm not sure if the game has an option to turn v-sync on, try that.
You can also force it on in the graphicdriver, just click on the game there or if there isn't make a profile for the game executable and enable v-sync there.

If it still runs too fast see if you can use the framelimiting option of your graphicdriver, 60 or 30 fps should do the trick.
Probably won't work well if v-sync is enabled.

Ok, thanks for your answer.

My System is Windows 8.1 with an RTX 2080 and a Monitor that runs at 144 fps. If the game speed is tied to the frame rate that would explain why it runs too fast. Although the newer nVidia drivers have an option to limit the frame rate (say to 60), they dropped support for RTX cards on Windows 8 a while ago, so I cannot use the frame limit build into the driver because my driver version is too old.

I might upgrade to Windows 10 eventually, but not right now and not just to play a single game. I will see if I can find another tool to limit the frame rate in the meantime.

RTSS (Riva Tuner Statistics Server) which is part of MSI Afterburner has a framelimiting option also, try that.

Yes, RTSS seems to work well. I set it to 60 fps, reduced mouse sensitivity and now the game is finally playable :)
Cool.

Yeah, I played through the whole game now. I also installed a high-res patch, altogether it was quite playable after that (still the letter box bars are annoying, but I did not invest the time to try out any of the fixes as they seemed more complicated).

Cool game, although maybe not quite as great as Giants. But I had fun playing through it :)