Inkscape Forum Inkscape > Flowchart question

Hi,
 I am trying to draw a flowchart of the form:
   <----------------
  |   _____      __ |__
  |  |     |    |     |
---->|  A  |--->|  B  |--->
     |_____|  |_____|

I modified the example in the user manual to:

size(300,100);

import flowchart;

block b0=rectangle("",(-1.5,1));
block b1=rectangle("A",(-1,1));
block b2=rectangle("B",(1,1));

draw(b0);
draw(b1);
draw(b2);

add(new void(frame f, transform t) {
    picture pic;

    draw(pic,Label("FF",0.5,N),
       path(new pair[]{(-2.,1),b0.left(t)},Horizontal),
         Arrow,PenMargin);
    draw(pic,Label("F",0.5,N),
         path(new pair[]{b0.right(t),b1.left(t)},Horizontal),
         Arrow,PenMargin);
    draw(pic,Label("E",0.5,N),
         path(new pair[]{b1.right(t),b2.left(t)},Horizontal),
         Arrow,PenMargin);
    draw(pic,Label("R",0.5,E),
        path(new pair[]{b2.top(t),b0.top(t)},Vertical),
         Arrow,PenMargin);
   draw(pic,Label("P",0.5,N),
     path(new pair[]{b2.right(t),(+2.,1)},Horizontal),
         Arrow,PenMargin);

    add(f,pic.fit());
  });

However, the resulting flowchart (pdf file attached) has several 
problems:
- the line connecting the block labeled B to the unlabeled block b0 
(which I would also like to reduce to a point) seems to be connected 
directly horizontally from b2 to b0 and not as a vertical followed by a 
horizontal then vertical segment from the top of b1 to the top of b0,
- the lines drawn to connect to the left of block b0, and the line from 
the right of block b1 (labeled B) do not seem to be consistent with the 
specified coordinates, and
- I am unable to independent specify the size of the blocks.
I would appreciate any suggestions to fix these problems.
Thanks,
Recif