Download it instead. On a mac, ctrl-click. On a pc, right-click. Then save the link.
Doesn't work like that on Windows 8 with Firefox. Pretty much every right click option offers to save download.htm which is not the script itself. What works best for me (most of the time) is to left clink on the script link at http://sourceforge.net/projects/bumcheekascend/files/, wait 5 seconds and then my browser offers to save the file or open it in the default application, at which point I save it.