I've integrated the Adafruit Xbee adaptor into my own Arduino Mega carrier board, and seem to find that I cannot upload software into the Arduino (via its usb port) unless I remove the Xbee chip from its socket. The only connections I have are RX-TX, TX-RX, 5V to +5V and GND to GND.
Is there anything obvious I might have mis-wired, or ideas of what to look for? I used the same xbee and Arduino with a Libelium adapter previously and I had only the same connections, which makes me fear I may have screwed up something in the adapter circuit during the process of integrating it into my eagle file.
Any thoughts greatly appreciated!
-Mark M.

