Lee sez:

I had another problem with my flap though.  As you said the screws 
which hold the flap to the shaft come loose.  I noticed that the screws
were NOT locating on the flats on the shaft, in fact the flats were
180 degrees out.

- This is the way it's suppose to be.  I noticed that on mine also.
However, the "rod cages" or the places where the lever rod slides through
on the flap have a flatten area opposite the threaded area where the screws
come through to bind the rod against this area such that the rod's flat
area mates with the flat area of the "cage".  I'm replacing the screws
with an allen head screw (I know it's not stock, but....) so I can really
tighten them down..

christian