Need to customize graph layout

We are evaluating gojs graph layout to draw flow diagram and could able to render the diagram(shown below) but there are few short comings:

  1. The split node sometimes doesn’t appear at the middle of its immediate children.
    2.There are few extra edges/elbows in the diagram.
  2. The split node and the point where arrows meets are not in line with each other.
  3. The diagram is not symmetric.

We have tried lot of options which comes with LayeredDigraphLayout but finding it difficult
to meet al the above points.

The diagram should nearly look like the second diagram shown below.
My question is, would it be possible for gojs team to customize LayeredDigraphLayout
for us (on purchasing the library) by taking into account the above points.

This is what we are trying to achieve:

See my reply to this similar topic.