I was able to recover the squirrel by reflashing it with FW again, so I tried to set it to bridge mode, but nothing would get captured. I set it back to transparent mode, and it failed to capture anything, so I reflashed it again, which fixed it. I don't think it likes to be changed to Bridge mode, or I'm doing something wrong, but I don't see how that can be.
Oh well.. It was worth a try