NuMenu4u and DVDAuthor?

[Zeul]

The time is coming when i will be offering a freeware alternative to scenarist authoring in NuMenu4u. The obvious choice is dvdauthor, but the documentation is limited on sourceforge. Does anyone have a link that shows all of the VMI commands currently supported? I understand that the GOTO command is not supported - is this still true? Seeing the syntax for the commands would be usefull too.
Also is there the provision for programs within a PGC? All aspects of the PGC need to be supported so that the xml can be a full breakdown of the ifo, example pgc still, goup command etc etc.
Is the GPRM limitation still true?
How are slideshows dealt with? Scenarist doesnt allow chapters in a slideshow stream which has always been a PITA.
How are seamless cells specified?

I would appreciate all suggestions & comments.
thanks in advance
Zeul

[Zeul]

no one has any ideas?