We can learn from this and include it in the manual.
For sharing sequences with model groups, the shared group should be set to "Minimal Display" ?
Well, it kind of depends on what you are looking for.

If you want the group setup in such a way that you can turn on the "left half" of your display via the X/Y coords on the color wash, you would not want the Minimal Display. The would turn on the left half of the minimal area of the enclosed models, not the left half based on the whole preview.
That said, this shows that I'm missing options for the Buffer Types for the Model Groups. Right now, "Default" depended on what the group is set for and there isn't a way to select the other. This should be updated to force the use of Minimal or full on a per effect basis.