If your "Have a Coke" light is on & you can't pull a bottle out of the stack, then it looks like you may have your wiring connections bass-ackwards on the stacks' vending switch. (down by the vending solenoid) reverse the wires on the terminals marked NO (nomally open) & NC (normally closed) this will turn off the "Have a Coke" light & activate the CREMS so the coinmech' will accept coins,
Once the vending price is reached, you should hear the stacks' vending solenoid "Click" & the "Have a Coke" lamp should light up agian until you remove a bottle, then it should go out, and teh coinmech should accept another coin(s).