Relay Shield (DFR0144) and LCDKeypad Shield (DFR0009)

I have an Arduino UNO v3, a DFRobot Relay Shield and a DFRobot LCD Keypad Shield.

I have reconfigured the Relay Shield to use digital pins, D0 - D3.

Both shields work perfectly, by themselves.
In Other Words,
I load a sketch on the UNO that controls the LCD and the Relays.
If I plug in the LCDKeypad into the UNO, it works perfectly.
If I remove the LCDKeypad from the UNO and then plug in the Relay Shield, it works perfectly.
If I then plug the LCDKeypad into the Relay Shield, the LCDKeypad display does not work. The buttons still control the relays correctly.

Here are the lines in the sketch I use to declare/init the display / relays:
LiquidCrystal lcd (8, 9, 4, 5, 6, 7);
byte relayPin[4] = {0, 1, 2, 3};

And then in the setup() routine:
for(i = 0; i < 4; i++) pinMode(relayPin[i],OUTPUT);

delay(200);

for(i = 0; i < 4; i++) digitalWrite(relayPin[i],LOW);
delay(2000); // grasping at straws here

lcd.begin (16, 2);


* Initially, on powerup, the display backlight lights and the power LED on the LCDKeypad is on.
* After about a second, the backlight flickers a bit and then goes off. The power LED on the LCDKeypad turns off with the backlight.
* Then, if you press any button, the backlight and the power LED turns on, but no text is visible.
* The power LED on the UNO and the Relay Shield are on all the time.

The voltage provided by the USB port is not really adequate to power the Relay Shield. I am using a separate, 9V power supply to power the UNO and the shields. After I put the sketch on the UNO, I disconnected it from the computer.

I am not sure if this is relevant, but if I try to load a sketch on the UNO when the Relay Shield is plugged in, I get the dreaded:
"avrdude: stk500_getsync(): not in sync: resp=0x00" error.




PLEASE HELP!