Two thoughts:
First, since the SD card didn't make any noises or have any affect at all, I would have to question if the SD card is set up correctly. Could you explain the steps they told you to follow? First off,
make sure the battery is fully charged, then make sure that you're putting the files at the top level of the SD card and not in any folder. Ideally the card shouldn't have a bunch of other stuff on it, but not an absolute requirement. And if they had you download a .zip file, be sure it was unzipped, and again the files shouldn't be in a folder.
BUT, before trying a firmware update I have a safer suggestion!My second thought is that since the little guy was moving around up on the shelf in the middle of the night, he might think the back leg is hurt. Pleos are programmed where they can get "hurt" they will act like a leg has been injured and just like other animals with sore legs, they will lift it up. The first thing I would do is turn on the pleo and try touching the sensor on the front of the leg. If the pleo starts crying and whining, it has a hurt leg. It just needs to be "treated" (should be covered in your companion guide), and will get better in a couple of days/battery charges. You can also try
running a skit or use the
Probe RB tool. If the leg returns to normal while running a skit, then the leg is mechanically fine and Probe RB should identify if the pleo thinks it's leg is hurt.