Based on the information found on the official website, the software is not compatible with Windows 10. The latest version is compatible with Windows Vista and Windows 7. There is no mention of Windows 10 compatibility.
Download the application using the following link: http://mpgravity.sourceforge.net/ and then launch the installation as Administrator. Right click the setup package and choose Run as Administrator, then every time the application is started, you will have to run it as Administrator as well.