Noob regulator Questins???

I just got my keg kit http://www.midwestsupplies.com/products/ProdByID.aspx?ProdID=7739and have some regulator questions. One is when I went to pressurize my empty kegs to check for leaks I slowly tried to raise the pressure to 30psi. While I was doing this, the regulator started sputtering and the needle on the gauge started jumping all over the place. Then the overpressure thing went off and scared a few drops out me. So I tried it again after bleeding off the pressure, this time slooowly raising the pressure, and sure enough the same thing happened. So I filled the keg with sanitizer and did it again but this time everything was fine. Then I disconnected the pressure at the keg and turned off the gas on the tank and the needle on the regulator maxed out and stayed there till I bled the pressure off a few times. Does the regulator have problems or is this operator error???

Second question is, after I racked my first beer into the keg at room temperature I placed the keg and Co2 tank in the kegerator and turned on the gas. I checked it the next day and the high pressure gauge that read 1200psi at room temp now reads ~600psi. I figured it was a leak so I rechecked the keg and tightened everything up and the gauge stayed, so I figured problem solved. Then just the other day I took the tank out of the fridge and set it back out at room temp overnight and what do ya know, it rose back to 1200psi???? Is that normal??

The first question is really bugging me. But it is dispensing beer now so I can RDWHAHB.

1. not normal. make sure your regulator valve is CLOSED (not allowing gas out) when you open the valve on the cylinder. failure to do this can damage the regulator. Also make sure you have the nylon washer installed.

2. normal. search the forums...gas pressure is directly related to temperature. as temp decreases, pressure decreases. at 70F, CO2 should be at 900psi. at 40F in the kegerator, it should be more like 450-500psi.