Ok, I finally got it work, I think. The advice about not holding the button for more than 2 seconds was spot on. I think the instruction could probably be written a bit better for those of us that skim over instructions. 🙂
Upon installing the drive, I got the message that “Windows can’t verify the publisher of this driver software”, and I clicked “install anyway”. This part seems pretty normal, as I’ve seen this before. But after that, I get the message that it can’t verify the digital signature. What? I thought I just took care of that! I’ve never this happen before. So ended up following the Windows 8 instructions for disabling signature checking, even though I’m running Windows 7.
I ran the updater, and it produced some errors. Unfortunately, the updater won’t let me copy the output to the clipboard, so I guess I won’t post it here. But the device says it’s running 2.0.7, now, so I guess it worked.
All in all, I have to say this was a rather painful process. Is it possible to implement a network firmware update mechanism? Perhaps save the firmware image to the SD card over the network, and then reboot and have the boot loader update from the SD card? A no-tool/no-driver firmware update would be so much easier to use.
Also, I really didn’t like that I had to download a 158 MB zip file (that unzips to 455 MB) containing all sorts of stuff I don’t need. I would much rather download just the tool and the firmware that I need.
Anyway, OpenSprinkler otherwise seems like a great product!