I have the exact same point of wear as shown in the picture in my X5. I have about 3.5k rounds since upgrade. I also have a pronounced "silver" track along the slide from the disconnect divot forward.
In cleaning, I lay a track of Lucas Grease along that track and a dab in the divot.
I have occasionally had the slide fail to return to battery by about ⅛". To be clear, I don't know for sure that the Puppet Head is hanging up in the worn screw hole as shown in the picture, but I suspect it is.
As a note: I "stole" your picture and posted the same question on SIGTALK to see if anyone there has seen this type of wear.