Hey, Tito76, thanks for pointing this out!
I completely forgot to support Windows XP. This game will be updated some time this week, and I will try to add support for Windows XP back in.
Once the new build is live, I will let you know.
Thanks for your patience!
[EDIT]
I managed to submit this game right before the deadline. It has no Windows XP support. If there is significant demand for such a version, I will make one later. This project really needed to be submitted before the deadline, hence I did not experiment with Windows XP.