pics would be good or maybe a diagram of how you have it wired.
Robert: On the ncp 630a, the control pin has to be tied to a low state. Thinking in digital terms, low is a 0v and high is 5v. (it's actually a bit different with the newer circuits working at lower voltages but it's the general idea). If the pin were left floating, the output could be on or off intermitttenly, so tying the control pin low makes sure that the regulator is off.
The reason for the resistor.. If we had the control tied directly to ground without he resistor, when we apply a positive voltage to turn it on, we'd have a direct short to ground. the resistor stops that from happening..
hoog