I asked too here (link) and never got a reply …the problem is that the filters that the ratDVD developers released is only a (pre-compiled) DirectShow-filter binary, (not the full source code to the codecs nor the muxers/splitters), and VLC, MPlayer, XINE, etc. are not DirectShow-based so do not support DirectShow filters nativly (because DirectShow is Microsoft Windows propriotory and copyrighted). …so best would be if the ratDVD developers open sourced their codecs and muxer/splitter so that non-DirectShow players can playback ratDVD.
PS! I very much doubt that ratDVD don’t use any code at all from GPL/LGPL codecs, (or take advantage of the patents/specifications held in copyright by the MPAA for MPEG-2 and MPEG-4, or Dolby for AC3), but if they don’t they don’t have to even release the source code of the codecs they have created from scratch, however if they just used a single line of code from a GPL’ed project inside their codec code then they must comply with the GPL license and release the full source code …they managed to legally workaround the GPL with libdvdnav and imdbexport by encapsulating the code inside a COM server to dynamicly load these when needed (do I don’t see any ratDVD headers for them which they technicaly should have released too) however I don’t see how they can ever get around it with the GPL and other licenses and copyrights of existing video and audio codecs without violating numerous copyrights and even laws, …I don’t know maybe they plan to release the full source code soon in which case I pre-apologize now, I hate to sound like a OSD-zealot but I’m really disappointed that they are still holding on to the should code