Default search depository
I use a fair amount of Japanese source material. When I do an ISBN search for that source, it begins to look in Library of Congress (understandably since it probably is the largest or equivalent to the British Library). However, I would prefer it to look in the Japanese National Diet Library so I get my sources quoted in Japanese (now I have to edit title, author etc for hand since it is transliterated into Latin alphabet.
Fortunately there is apparently a work-around: in the detailed view of a document, click on "Output Bibliographic Record" and select a format supported by Zotero. BibTex can be opened directly, MARC might provide more extensive metadata but I think you'll need a few more mouse clicks (File/Import... and a few more steps).