Files are fine , xml was not updated , I just uploaded the correct xml version.
All you need to do is reinstall the one file you get from download area which is
Multimedia Box Package for Joomla 1.7 and UP
but this tells me than that js in plugin is ok and something else is causing the issue
Do me a favor please
post exact news item content as you have it in your editor once you are in Article manager
or like said PM ( private message ) me with admin info so that I can take a look and duplicate your settings on my end to test further.