Thanks so much for the assistance, AnemicOak.
I was able to install Aldiko, and to get ADE to see the Vox. ADE said it was copies the ebooks onto the Vox. So far so good.
However, it doesn't show up in Aldiko, and when I manually direct Aldiko to look in the most promisingly-named folder (/Ebooks/<name-of-book>/) it says "No EPUB or PDF file found". Any thoughts? Thanks again.
ETA: It's all working now. Thanks so much!
BTW, what does "ETA" mean in this context? I've gathered it's an edit after the fact from how it's used by MR contributors, but I don't know what the exact acronym is.