Thanks Francissimo! My PS files get pretty big too, but fortunately I've got a powerful computer which (so far) has taken the strain.

Thanks for posting the large size version which allowed me to see more how it was done. Of course the image should not be viewed at this size for beauty. If there are aliasing and the bevel and emboss roofs to buildings, they are much better seen zoomed out than close up for sure. There is so much in this map to love in terms of how the elements are distributed. Great stuff!