I would probably choose the dynamic gallery and make use of all the BB types to have a gallery aligning with each body area. eg Autotext = Ankle; Custom Autotext = Core; QuickParts = Knee; etc.
If you go with the BBCC then you can create your own categories within the one BB type but I think the useability is less intuitive.

With the pagination, are you changing the page setups and adding section breaks? You had mentioned previously that you wanted some portrait and some landscape layouts and this would require section breaks if in the same doc. But then again, it also appeared you wanted to send each exercise out as a separate file which didn't sound like it was the best solution.

The pagination shouldn't change from saving the doc and closing and then reopening. That could conceivably happen if styles updated on open but not if the same template was still attached. However, changing printers 'can' cause pagination issues especially if opened on a different computer. You avoid this issue by making your 1 page exercises fit easily on the page (with a little extra space to spare) and include a 'Page break Before' setting on the style used for the exercise title which ensures it always starts on a new page.

I would highly recommend you make all exercises fit on the same page setup (either portrait or landscape) so you don't make this more complex than it needs to be.

If you 'must' go with a mixture of portrait and landscape, you will need to include a section break after each exercise since this is where the page setup info is stored. That section break would need to be included in every BB you store.

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Andrew Lockton
Chrysalis Design, Melbourne Australia