I also have been flying the hanger 9 Edge 540 for sometime now. Mine shows none of the symptoms you describe. I can slam the plane into a perfect wall and parachute maneuvers without any snap what so ever and this is using 3" of throw on the elevator. From reading your posts I have comeup with a few things to look at.

1. Is you wing truly straight. I say this because the main wing thickness tapers on both the top and bottom of the wing. So when this wing is truly straight it will look to have a little antiheadral in it. I find it easiest to site the wing from the tip of the wing and look down the leading edge of the wing. While doing this also check the curvature of the leading edge of the wing for uniformity. If this wings leading edge is not uniform in shape it can cause the situtation you are describing.

2. Move your CG foward to 4" to 4 1/4" from the leading edge of the wing. Is your plane balloning when you cut the throttle? If so it is a sign of a tail heavy condition which would make the elevator alot more sensitive possibility causing the snapping problem you described.

3. Fix the incidence on the elevator by shiming the mounts to the main wing. The wing and elevator should both be 0 degrees.

4. Check the movement of the elevator halves in relationship to each other. Are they moving together or is one of them moving farther or faster than the other?

Take your time and get these items fixed before you chance flying your plane again. This is really one of the best flying 1/4 scale planes made (especially for 3D) when setup properly. Let us know how things go.