That is a good question and I don't have a good answer yet. Here's the issues.
The first option is simply what I'm currently doing, saying boxed sets and multi-packs are not synced from DVD Profiler.
I've thought of allowing multiple DVDs to have the same ISBN then provide a shadow title that if defined would be synced to the LinuxMCE Title attribute. I just don't see how to get the shadow title from DVD Profiler so would have to provide UI for manually setting. Same for images. This is a limitation of DVD Profiler, i.e., one ISBN, one title, one pair of cover images.
I've thought of using DVD Profiler's Discs fields, but their usage just doesn't seem to fit.
Here's some examples:
The Adventures of Indiana Jones
** Indiana Jones and the Raiders of the Lost Ark
** Indiana Jones and the Temple of Doom
** Indiana Jones and the Last Crusade
* Only the collection box has an ISBN, the individual disks do not
* The three titles are only listed in the Overview
* There are no entries in the Discs section (I know, correctable)
Back to the Future, Ma & Pa Kettle, all have the same style
In Broken Trail, the feature is on two discs and the Discs sections is:
1 Main Feature: Part 1
2 Main Feature - Part 2
A lot of single titles will have Discs sections like:
1 Main Feature
2 Bonus Materials
TV series usually will fill in the Discs section like:
1 Episodes 1-7
2 Episodes 8-15
The only other option I can think of is to replace the box sets entries in my DVD Profiler database with individual entries. In other words force my DVD Profiler database to only contain one title per ISBN. That still doesn't work on epic movies that take two DVDs.
While I'm leaning on the first option, I'm open to any ideas here.