chr, thanks for all your efforts thus far, it's much appreciated by all. Like tracer, i'm a programmer too (but C# rather than Java).
I'd be more than happy to help any way I can. I've got an IXUS 80 IS too, which I don't mind using to help test out/load stuff onto.
tracer: Looking at the Wiki, CHDK is written in C. Although the wiki also mentions assembler knowledge is required to add new camera support to CHDK. Hrmm...