I experimented a bit more this morning, and everything seems to be working, both for the 2400 and the 7800. I put the profiles here: hard drive/library/application support/adobe/color/profiles/recommended. As I noted above, I am using Maverick, and this article is what led me to put the profiles where I did: http://www.drycreekphoto.com/Learn/profile_install.htm In the Adobe file, the subfolders color/profiles/recommended did not exist, and I created them.
I know all I've described sounds silly, and others more computer savvy than I may find something terribly wrong with what I have done, but, at least obstensibly, it works, and I have what I think are ICC profiles for the 7800 for the first time since I've owned it.
I welcome any adult supervision!
Thanks again, Kurt, for your help.
Mike