I think it loks great! I don't have an answer for you about the 'dirt
layer' but I hope you figure it out. The only nitpick I have is that the
writing on the desk is too neat. There are a ton of free fonts on the
internet that have a scribbled scrawl look; one of two of these would make
the writing more realistic. Try changing font sizes as well as font types
too.
Rich
