We have the 16-bit/24-bit problem still. I'm using rev. 492.
I have until recently in Puppy Linux been using mplayer compiled with '--disable-gui', and instead using the 'gnome-mplayer' frontend for mplayer. That works ok.
However, yesterday I compiled mplayer with '--enable-gui', and found that with 16-bit color depth I just get two black windows. The two windows that display are the video-rendering window and the control-panel. By using the right-click menu I can still play a video, it is just that the video-rendering window appears black initially as the splash graphic does not display. The control-panel stays black.
I switched to 24-bit and it all works.
Note, if you have mplayer installed, with gui enabled, it can be run from a terminal by typing 'gmplayer' (which is normally a symlink to 'mplayer' that runs mplayer in GUI mode.