Hi Suzie,
I looked at your genetics chart and Punnnet squares.
You are on the right track .... but not quite right.
The main thing here is the the E down color gene and the lavendar gene are different genes. So when doing your Punnet square you have to account for both sets of genes.
In this case the down color gene is the same for the black and lavendar color birds.
So for the F2 chicks you would have:
25% black (EE, LavLav) -- Lav, with capital L is non lavendar,
which is Dominant to lavendar.
50% black, carrying one lavender gene (EE, Lavlav)
25% lavender (EE, lavlav) -- lower case lav denotes recessive.
The Lavendar gene doesn\'t change the EE down color gene, but changes how it is expressed.
Curtis