First of all. Thank you very much for your donation. It's really much appreciated
Just as GearBunny said, this is often a problem with games and programs developed by unknown developers. The game is completely safe, as MalwareBytes says. I'm guessing you are on Windows. If that's the case you should see either of these to screens:
If you see the first screen, you need to click "More info" to get to the second screen. Then click "Run Anyway"
I apologize for the inconvinience