Product review (4 stars): I then gave the problem edge a good whack. It snapped in properly
The new panel eliminated all the freezer's misbehavior.  Installation was complicated by the attachment system, and requires more force than one may think.  Removing the old panel required prying it off. I used a putty knife, screwdriver, and, to avoid scratches, painters tape.  That did not work until I applied sufficient force to break the unseen tabs holding the old unit to the freezer.  Breaking the tabs caused concern that the new panel would not be held in place.  I aligned the electronics and pressed in the edges of new panel, but it did not snap in.  I then gave the problem edge a good whack.  It snapped in properly.  I plugged in the freezer, and it started working properly.