Newbie question GX developer

I am using gx developer ladder

here is the problem
http://imageshack.us/photo/my-images/233/solinoid.jpg/

Mine version not work

http://imageshack.us/photo/my-images/231/singel1.png/
http://imageshack.us/photo/my-images/804/singel2.png/

Mine friend version work, but he dont tell me why thoose internal relays M are in parraleel, and why 3 times M0, and why M1,2,3,4,5,6 to Y000, how do u know what M to what Y
http://imageshack.us/photo/my-images/821/parrell1.png/
http://imageshack.us/photo/my-images/8/parralell2.png/

you need to write your own flow chart to work out what is happening.
your friend has written code for a step sequence.
His code does not match the original problem.
I read that program differently
3 or 4 inputs (X) Maximum
3 outputs (Y) Maximum
and 6 Timers

UNLESS THERE IS INFORMATION MISSING

Your Friends program-
the M contacts in paralell is purely to keep his outputs ON as the sequence continues,
But, I believe too many i/o is used