Mine sits down properly. Something is preventing yours from sitting down properly. What I would suggest is for you to unplug that USB drive, flip it over and remove the bottom of the chassis, remove the two small screws holding the board down and then remove the board completely (the heatsink-fan unit should lift with it). Then, you can examine the chassis to see whether there is something out of place that is causing it to not line up properly.
Your other alternative is to either return the unit to point of purchase for replacement or contact Intel Customer Support about a RMA replacement via mail...
Hope this helps,
2 Screws? Or... 4 screws in corners of motherboard.
Why so complicated? The top cover can simply be removed (and is designed to be replaced) by removing the top 6 Torx screws and lifting it. That way one should immediately see what's causing the problem. From the looks of it it may be the main wifi antenna which sits about where the bulge is.
Found it! Duhhh! When replacing the top cover one has to make sure to get all the tabs in the top cover on the correct sides of the perimeter shield. The tab marked in red must have pushed up the perimeter shield causing the bulge. I noticed that the bulge in the top cover was gone when I opened the bottom to perform your check. All is fixed.
Thanks for the indirect help, ;-P
Yes, 4 screws (I presumed same as other chassis; I should have just looked)