Hi Enzo,
First off, Thank you for your purchase! 🙂 We had 2 other users report this, we will look into the issue, the other 2 got the installer to work after restarting their PC, this is obviously not how it should be but it can be a short term fix for you while we try to figure out what is going on. While I'm typing this I see you did exactly that. Thank you for thinking ahead 😄
Kind regards