SiG,

This is a good candidate for the pressure test Looks like you have more pressure in the upper left on the last sink pic and a kind of pooling of thicker paste on the rounded edge lower right. If the sink was flush you would have no accumulated paste or the rounded edge, it would have squared off under pressure. Hard to tell from the pics, pressure film will indicate whether I am right or wrong on this.

It does seem Like the "Fan" out from one corner type mounts are giving higher temps though.