You don't need any download manager to download the game because the installation package has only 10MB. Right-click on the installer, select Properties and check the information from Type of file field. If it is a SWF application right click on the file and open it with Internet Explorer. Also, you can drag and drop it to any opened browser. If it is an EXE file, and you're using Windows XP or below, try to update Windows Installer. If you're computer runs Windows Vista or above, update Windows Installer through Windows Update and run the application using Administrator rights.