Ok I built the inner steps in 2 minutes....first I just made a cube to experiment with. I then duplicated and shifted in Y to JUST below the top of first cube...I then took note of the Y distance and tried that in duplicate special...X and Z scale at 0.9 and Y scale @ 1 I then Y translate the distance I noted. This didnt work entirely as the blocks were not on top of each other but seperated. I then just played with the Y translate until they sat on top of each other..with a little overlap. I set dup>special to 5 as a test...and presto it worked. You could delete the bottom face as it isnt needed...I assume CG that after UV the first one...the dups should have the UV laid out as per your instructions?? You could do this with the other steps...then maybe use 'cut faces' to delete ones not required.

cheers bullet

EDIT ok found a glitch...doing it my way will not give an even slope....so that wont work...you may have to script something to get the slope to be even and not convex, concave...sorry mate I tried.