It's exactly as described by
dabossofall200157302dd in post #6 of this thread or also the initial post by
andreibibo154602e3 is sounding exaclty like the same issue. I will draw a scematic which I will extemely exaggerate so you understand what is going on. The exact model I have is the GF63 12UC-667.
View attachment 187510
Or compare with Crazydonkey (post #7) who says following: "If you hold the touchpad and press it directly, then you won't feel the two-step click".
What he says is, when you hold the touch pad, so that the gap indicated by the red arrow, is closed, the touch pad feels absolutely normal likey other touch pad. Unfortunately the touch pad wasn't fitted perfectly.