guessing that the 2 plines define a distance that the block must fit between, 
one could search for the 2 plines in the area of the desired site, find the 
pline segments that would intercept some lines that constitute an outter form 
or boundry of the block, then set the size and orientation of the block 
insert from the intercept points. Again guessing, the bkock form would most 
simply be on line, or axis, and the intercept points are the 2 (inters 
axislinept1 axislinept2 segmentpt1
segmentpt2 nil) for each segment. The code for this would be about 100 lines, 
more for non parallel plines or 3d block boundry forms. Our company, AusCad, 
does this for our living. We do the drawing instead of selling programs 
because there are few applications of each programing effort. a phone # is 1 
410 5253992. Have at it, the process can be automated, its just a matter of 
time.
--- Amie v0.93
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