There are a couple of things in play here:
- As @superfell said, Chrysalis prior to 0.11.3 had a bug that made flashing not work, at all. It backed up the EEPROM contents, cleared it in preparation for flashing, but flashing itself failed. That left the keyboard in a half-bricked state.
- The current firmware also has a bug where saving… pretty much anything larger than 32 bytes can cause data loss on the firmware side, which manifests as corrupted data saved. We will have a fix out in a couple of hours.
- If flashing with the Arduino IDE, the Arduino IDE doesn’t know how to put the Model 100 into programmable mode (yet), so you have to do the hold-PROG-while-plugging-in trick @msarahan mentioned above. We know how to teach the reset sequence to the Arduino IDE, we just didn’t get around to implement it yet. This will be fixed soon, too.
It is really, really, really hard to completely brick the Model 100. Even intentionally. And accidentally, that’s practically impossible. There is always a way back, even if your firmware ends up crashing on boot. As long as you do not overwrite the bootloader (not possible without specialized hardware), you can restore it.
The PROG key is always PROG, no matter what you map it to. What matters is the location of the key (first key on the first row on the left half), not what it is mapped to. It is handled by the bootloader, not the firmware, and the bootloader doesn’t even look at the keymap. The bootloader is also something you can’t overwrite without specialized hardware and explicit intent.
In short, my advice for now would be to wait a few hours until I release the updated firmware. I will make an announcement topic here on the forums once I’ve done so.
When the firmware is out, you can start up Chrysalis, go to Preferences, enable automatic firmware updates, which will then download the newest firmware, and will offer it for flashing once we get there. When the firmware is downloaded, unplug your Model 100, hold the PROG key, plug it in, and then Chrysalis will be able to connect to it, and will offer you to flash new firmware. Select the new firmware (it will be version 0.90.1), flash it. Then, to make sure you’re starting with a clean slate, go to Preferences, then My Keyboard, and hit the “Reset to factory settings” button. There’s currently a bug where that never “finishes”, but you can restart Chrysalis after ~10 seconds, and you’ll have a working keyboard.
This isn’t the easiest process, but hopefully you won’t have to repeat it ever again. (Or if you do, we hope to make the restoration process much smoother in the not too distant future)