Unable to access bone tutorial .sifz file

So I was trying to do the ‘Basic Bone Tutorial’ listed on the wiki (Link http://wiki.synfig.org/Doc:Basic_Bone_Tutorial) but upon scrolling to the bottom of the page, then downloading and opening the zip file, it opens a file titled ‘rigarm’ that opens the Terminal and seems to do nothing else.

Does anyone else have this problem? I use Mac OS El Capitan. Any help would be greatly appreciated.

I tried it on Windows 10, Synfig 1.3.1 without problems.
Here is the original file I created for the tutorial. Try and load that to see if that works.

rigarm.sifz (9.26 KB)