See
and,
and, possibly others.
Starting MM as "Run as Administrator" and double-clicking *.mmip, results in second copy of MM starting and window stating that installation failed.
Setting "Allow just one instance of MediaMonkey" has no effect.
Selecting "File" -> "Open URL or File" and browsing to the .mmip does not work either; nor does attempting to drag-drop the mmip to MM; nor do variations of UAC On/Off.
Script installations on same computer with V. 3.07.1191 worked.
Dan