The solution
Assuming that no other compatibility issues would arise (not a safe bet), an architectural picture was emerging: separate folders containing largely redundant content for different platforms. These at maximum include an ISO9660 folder, a standard DVD-V video_ts folder and (if any non DVD-V files are required for MX04 ROM play) the ROM product directory structure with it's own video_ts folder.
This reduces the grey areas considerably. Now we're focused on resolving the Mac DVD-V play issue and we're interested in how the similar issues effect non-Windows and set-top platforms. It also looks like compatibility issues don't effect key functionality for our most crucial platforms OR workarounds exist for same. Additionally, the probability of increased future support is high.
Based on the cumulative experience of the gurus, the ROM should be able to use the same video_ts folder and Director needs place non-standard content in video_ts. Moreover, experience suggests that set-tops will ignore all non-standard content be it in or outside a video_ts folder.
Testing would be required to conclusively determine compatibility issues.
Space considerations:
I don't presently consider redundant content to be an issue with regard to disk space. The product is a serial, monthly release intended to keep consumers coming back for more and it's unlikely that Free Media will give away that much content in a single issue through current distribution channels. It is likely that this will change, however, as ad-customers determine content and these will exist for "one-of" or non-serial distribution through new channels. In this regard, any solution which reduces redundancy and increases cross-platform access to singular content is clearly favorable. Multilayered disks could be the magic bullet here, not used to "split" content for various platforms but to extend the storage capability of the disk. It's worth finding out production costs for multilayared DVD at your production house. Producing the premaster would require production capability you don't have yet but they might. If they don't, Steve Mendel does.
Solutions definition conclusions:
Despite some diverse conditions, solutions definition was remarkably streamlined. No challenger to Director MX04 has arisen for ROM production and other limitations force us to accept almost predetermined solutions. Any conflicts or functionality not supported by this approach will have to be borne gracefully until other options or extended support exist.
Looking forward, Sonic Solutions and Macromedia appear to be set for a head-on clash for dominance in this space. With all it's acquisitions, Sonic could head in numerous directions BUT they are pretty much forced to compete with Macromedia. This will render much of their IP and technology patents moot in the marketplace. As a driver of hybrid hardware development I think they are washed up. Bill Gates MIGHT have the resources to compete with Panasonic on a manufacturing level...if someone put something in his morning coffee. Macromedia's broad OS support advantages it tremendously. "Competitors" such as Pinnacle, Adobe, Spruce, etc. have too much catching up to do to be serious contenders for this project.
MX04 is it for the ROM side. The DVD-V side is best left up to the developer subject to the requirement for only DVD-V compliant files in the video_ts folder (if it's not duplicated for this purpose elsewhere).
This does leave much to be discovered, as in "what happens when people start playing it on convergent devices. Given as much of this is new territory there's not much alternative to trial and error. It's going to be a heck of a test matrix.