Yeah, what started out as light leakage apparently seems to be a bit of a bigger problem. Mine does the same thing. I checked with the RS manager I bought it from and he claims he will let me exchange it this friday when he gets more in, we will see.
As mentioned, a clear sign of the screen not being completely flush would be light leakage coming from the bottom of the capacitive buttons.
A very temporary fix is to "push" in the particular button which may be leaking light, this will cause the problem to fix for some moments, but go back to normal.
Though it's hard to tell exactly how much the screen may be raised, I have compared the top portion of the phone to the bottom, and the top portion appears to be recessed in slightly more than the bottom.