Yea - nothing like being clueless AND doing some off-the-wall task that few have done.
Try searching the forum a bit, I'd be surprised if there weren't some hits.
I'm pretty sure it's one of the XBees. I reset both of them to factory defaults as you suggested and I could light up the RSSI on the receiver with the PC side transmitter when I did a X-CTU loop back test. That suggested to me the receiver was getting the ping. But when I swapped them and I could not get the receiver RSSI light. I still don't know if it's a receive or transmit problem and maybe there is no way to tell.
Sounds like things work, partially -- one direction and not the other. But nothing coming back from the loop back test?
Anyhow, I ordered two additional XBees this morning from Adafruit. I live in NY State so hope to get them tomorrow. Right.
I started with two as well. Found out real quickly that wasn't enough
You mentioned abuse and it's possible I did damage one of them. I have my project bot inside a 13" hamster ball (more like a ferret ball) and it does crash into things. It's possible I broke it before I even got it powered up. I'm thinking of shock mounting the new one. Because it's relatively inaccessible I want to be able to program it and watch sensor data as it runs. Probably not entirely necessary, but certainly more fun.
I was thinking more about electrical abuse. I'd think a few bumps inside the ball wouldn't be a problem. As long as it's not going 60mph or something, LOL! Still, some rubber bushings or something couldn't hurt.
I'd be interested to hear what happens when you get the additional XBees, good luck!