Hello! First, perform some basic troubleshooting. Might your antivirus be blocking you from launching the .exe? You may be able to launch it if you add it as an exception to your antivirus or if you temporarily turn off real-time protection features.
If this does not help, then please e-mail us at support@milkplus.moe with the following:
- What exactly occurs when you attempt to boot it up
- A screenshot of what the inside of the Flotsam Song folder looks like