I would assume that all the sections of the planter would have to be the same number of rows?  Or can you set up each section like on a sprayer, IE. not the same size sections.

I am setting up a experiment planter and would like to put 6 rows on 2 three row sections and the other 6 on 6 one row sections.  I have two boxes with 4 vavles each and am going to install later this week.  So I was just thinking on this as it snows to beat hell outside.

If not I will just run 6 two row sections.