This question is mostly for BenJeremy,
But perhaps someone else can explain the answer.
The Developers.rar contains a file called Internal.xml
which appears to hold actionscripts. If I'm assuming
correctly, the entire contents of this file are already
compiled into the default.xbe that comes with Media X
Menu, and the file is just there to give ActionScript
developers something to reference.
And to use any of the scripts included in this file,
one only needs the default.xbe on the harddrive and a
mxm.xml or menu.xml file to call them from.
without havening to do any scripting.
Please let me know if this is correct.