Hi Frank,
We figured out the problem: somehow, some "smart quotes" (the quotes that Word uses) got inserted into the citation tag around the refcode attribute alongside some normal quotes, which caused problems with the HTML parsing when we loaded the collection. This can happen if you write the text in a word processor (like Word) and then copy-paste this into the HyperCities editor. It's generally a better idea just to compose your text in HyperCities itself, or in a text editor like Notepad, Notepad++, or TextWrangler on Mac. These don't add any extra formatting. Is it possible that this is what happened?
Thanks,
David