I appreciate the prompt and very clear instructions, but they lead to a new problem: I was able to do the upload, and everything appeared to go smoothly — except that once the upload was finished the blink apparently died (it won’t light up, either when connected to the publisher or when i re-insert the battery). So I tried again with a different blink, and got the same result. I have 24 blinks, so can do some more experiments, but this particular experiment seems like I probably shouldn;t repeat it again. Is there enough info here for you to guess what’s wrong now?
Edited to add: I believe I’ve fixed this. I noticed that the file blink-bios.hex was identical to blink-bios-168pb.hex. I replaced it with a copy of blink-bios-328pb.hex, published to a third blink, and it seems to work fine.
Is there a way to repair the two blinks I hosed?