I seem so close to success but I'm missing something trivial...
I have run the applescript, chosen the SD card, partitioned but now the script is asking to 'choose the CHDK autobuild archive' which seems simple enough--but I'm not sure just which file should be chosen: the parent file for the download? the contained CHDK file? the DISKBOOT.BIN file? or PS.FI2? (only the last two seem 'available')
Can you tell I'm a noob?!
Please help & thanks
Well, I sort of solved the problem myself--I used the instructions for installing chdk via Linux (Ubuntu, specifically) and it went very easily; done in 10 minutes. For those who follow with problems installing under OSX, I don't really know the solution but it was so straightforward with Linux I have to give it a major thumbs up.