I've been busy with another project and couldn't get to develop MPlayerOSX Extended.
To track the the issues I created a Trac for the project:
http://mplayerosx.sttz.ch/trac/
I've created tickets for all the problems I currently know of and if you have anything else, feel free to open a ticket.
The wiki also contains a documentation of my current build environment for the mplayer binary (and the problems I had).