For anyone interested, I ended up sending the display back to MO for repair. Apparently a transistor used in controlling the contrast level had blown.

As soon as I get it back, I'll be getting on with the rest of my LCD project: http://star-www.dur.ac.uk/~djrs/project

Hi, I recently bought an LK204-24-USB display and was very happy with it until it broke last night :( The contrast appears to have set itself to a very low value (see attached image) and trying to change it with uProject has no effect...

I think I may have inadvertently shorted the +5 and GND pins ...