He lives!!!
I was able to figure out the snapping; it was his back right leg. I played with him for an hour or so with his cape off and heard no clacking. Then I was able to reset him and go through the baby-juvenile stage with no issues.
However, when I put his cape back on (very carefully, and tried to make sure it wasn't too tight), the snapping started up again :/. I then removed the cape, gently moved the leg, and played with him again, and he seemed fine. Has anyone else experienced this? I guess he may just need to be naked when I play with him

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Anyway, things are otherwise going well! The batteries do fine, though I will take your advice to not leave them on the charger overnight; I'm familiar with this and try to not to it with my cell phones either and found the battery lasts a lot longer that way.
I have found his sounds to be a little annoying, and that I enjoyed his company more with the sound turned off...I feel terrible admitting that, but so long as he gets played with daily, maybe he won't take offense

. Plus, his sounds I found kinda throw me off as to what he might be trying to communicate, unless he gets better at this as he ages? He seemed easier to read with them off when I didn't have honking and squealing to make me second guess what his body language seemed to be indicating. I do feel like a bad parent for saying that though. Sorry, Arlo!
I did wonder...does he seem to know when he's being picked up or cuddled? I would hold him against me with his tail and neck parallel to my body and my hand supporting his rump and the other hand resting on his back. I read this triggers him to fall asleep, but he moves his neck around quite a lot in the minute or two it takes for him to sleep...does he intentionally cuddle, or is this just random? I'll enjoy it just the same, but my husband was like, "It's not like he knows you're holding him or that your face or body is there."
Also, does he have senors on his feet? I'd try tapping them individually to try and get him to lift them, or to guide him into the "ta da" trick, but he didn't seem to react.
In any case, I couldn't be more thankful for your tips on how to reset him and get his leg to stop snapping. He's very cute, and I enjoy spending time with him and watching him do his pleo thing on the coffee table

. Hopefully nothing else major happens that I need help with! I'll see if I can't post some photos soon

. Thanks again!