Susan

I've previously recommended you don't use footnotes for your particular documentation as you've described it. Now you also want to include graphics in the footnote area, I feel like it is worth suggesting it again. Sometimes it is worth taking a step back to consider the audience rather than remaining fixated on solving recurring problems caused by your earlier design decisions.

Have a think about how your audience will want to digest your content. How do they read the original text with/without your analysis? If you were the new reader coming at the document does a variable sized footnote and side graphics area help their reading flow or does it hinder? If they want to read the original text once and then come back for the analysis does that work with your current layout? Are they working on a computer screen, hand-held device or are they working on paper?

In my opinion the task you are attempting to complete is better done by using columns on the page and putting the original text on one side and using the other column to put your feedback content. From a design point of view, I think this would help you place your analysis content AND it helps the audience interact with your work.

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Andrew Lockton
Chrysalis Design, Melbourne Australia