Thanks Ixus, I posted a question on their support forum and they replied straight away:
Well, at first I thought the answer to your question was that the switch to google's geocoder made a separate country select box unneccessary. But in response to your message I tried searching for "London, England", and got no love. It turns out that Google does not really provide geocoding for China, Japan, or the UK. (See also here)
I've now implemented a "more options" link after the location search boxes, which will bring back the country dropdown for China, Japan, and the UK. In these cases, the gecoding will revert to the geocoder we used to use, which could handle the whole world equally.
Sooo, 'More Options' is there now.