The only place I've heard of someone getting arrested ever, anywhere in the country, is Naperville Illinois.  And that was for recording the police, not for tampering or touching the meter.  We have sold hundreds and hundreds or even thousands of meters.  People have very good luck at installing them and getting away from their smart or otherwise digital meters.  I would not worry about getting arrested - it just doesn't happen.

First, doublecheck that your meter has a tab with 2 screws in the back.  This is required in order to make the meter work on 120 volts.  Here is the diagram we have for the wiring:

Hmm, I don't see why grounded vs. ungrounded should make a difference in the Stetzerizer readings. I'm guessing it is something else (like devices on the branch circuits, or perhaps which phase(s) - legs - the branch circuits are attached to). Do you notice that many areas in your home are lower - around that 150-300 range - and then many other areas are up in that high range? This could be explained by the 2 hot "phases" or "legs" that come in to the house - A and B - they can be quite different in readings.