OpticsInfobase translator is also not working for me. It downloads the info, but not the pdf (instead firefox prompts me to open the pdf file or save it). I'm on MacOS Snow Leopard using Firefox 5 and zotero 2.1.8.
a new translator has just been pushed and both PDFs and search results are now working - this may take up to 24hs to update or you can use the update translator button in the Zotero preferences.
Any help appreciated!