Cannot get FCP Auto Tracker Perspective to behave.

I can use a lot of software to a reasonably professional level... editing, music, art, desktop publishing and CAD. But I am completely stumped by this plug in- it just doesn't seem to work at all, or I am making a fundamental error? I am simply trying to map a word to a wall (in an admittedly grainy old piece of footage) and I've wasted hours on this now... and made zero progress.

I pin/define my four corners.
I move through frame by frame, tapping the frame advance buttons, and carefully adjusting the pins.
I complete and check.

THEN when I supposedly should be able to scroll through this mapping to check, the pins go insane... leaping from one random mess to another, bunching up, or wildly elongating into long shapes- some pins shooting away to distances many times larger than the clip itself. Absolute chaos, with no relevance to the painstaking frame by frame adjustments I have just made?

WHAT am I doing wrong here? Is there some basic step I've somehow missed? Help.

This is a third-party plugin, and I have no clue what specific plugin you're talking about. Who makes it? Did you contact the developer?

EDIT: I just looked it up, that PixelFIlm Studios. There's your first mistake... Contact them about it, they're supposed to support their own products.

Get either TrackX from CoreMelt or wait until Sept 2nd to pre-order the MotionVFX plugin "mTracker3D".