It looks more complicated than that.
To name a few problems I noticed from your latest screenshot:
The tabs don't have their text filled nicely, the previous/next buttons are cut-off, in the top left of the title bar the usual information about the selected file(s) is missing. (or maybe transparency working incorrectly here)
It's a pity Microsoft seems not to have anticipated very well on the progress of hi-res displays, and developers will have to put in lots of effort to correct this.