I deal with very similar issues, so I thought I'd chime in.
Right now, we collect anything that might be considered a "supporting file" in our locally developed Digital Repository, which was built with EAD-integration in mind (though aspects of this are still being developed). As such, we currently try to capture every instance of a "patron request" for digitization from our Special Collections department and add these to our digital repository:
and also link those items to/from the finding aid.
So, my personal suggestion would be to start adding these "supporting files" to your ContentDM system and manage/integrate them from that end. That said, it would also be nice if this sort of planning was worked into EAC (though I really don't know the state of that working group), so that portraits and images from different institutions could be associated with particular authority files of EAC records (at least, that's according to how I like to think about the potential for EAC).
As for "supporting lists in spreadsheet form", I've been putting this into the EAD itself (rightly or wrongly) by means of the <index> tag when that information was available in electronic form. Here's a crude example:
[click on "View Index" in Box 1, Folder a]
We generally only use the "change tracking" element for a major revision rather than typo corrections. I'm not sure, though, that this is a good idea, but there's nothing in our particular system to make this sort of tracking tenable for the time being (I think that it would have to be automated in the system, much like revision control in a wiki, and this is probably something that we should have in place).
We currently try to update the finding aid for every new accession and put this info our <acqinfo> section. If a preliminary container list is done at the same time as the accession, then yes, we go ahead and put this into the EAD (right now, we separate our processed "container lists" from our unprocessed "container lists"). Here's an example (though we'll probably change the wording during our redesign, as right now we have "container list" and "preliminary inventory"):
From: Encoded Archival Description List [mailto:[log in to unmask]] On Behalf Of Michele R Combs
Sent: Wednesday, February 25, 2009 11:02 AM
To: [log in to unmask]
Subject: Supporting files, updates, change tracking
Hello all --
We are slowly starting to acquire various "supporting files" for some of our EAD -- images for the bioghist, supporting lists in spreadsheet form, etc. I'm wondering whether/how other institutions are tracking this kind of material.
I'm also curious if other institutions are using the "change tracking" elements of EAD (revisiondesc, change, date, item). How do you determine whether an alteration to the file qualifies as a trackable change? Simple correction of typos, or only substantive changes to the content?
Related to that, what about when you receive a new accession to a collection that has an EAD finding aid -- when do you update the finding aid to reflect it? Do you add it immediately as a <c01><did><unittitle>2009 accession</unittitle> with a box list? Do you simply add a statement in the Scope and Content, e.g. "Additions received in 2009 are not yet processed and are accessible by special permission only" ? Or do you not update the finding aid until the material is processed?
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Special Collections Research Center
Syracuse University Libraries
222 Waverly Ave.
Syracuse, NY 13244
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