Atk4 form Columns
===

I'm trying to use columns in a form.

I have the next code, that produces the ![Columns][1]


  [1]: http://i.stack.imgur.com/E0uIh.png

The code is this:

    $col=$this->add('Columns');
    $left=$col->add($f->addField('text','observaciones'));
    $right=$col->add($f->addField('line','cantidad_de_bocas'));

the fields of the columns, are based on form fields. I whant to add more than one field to the columns (ex. 2 fields on left column and 4 fields on right columns).

I have seen some examples about this, like 

    $col=$page->add('Columns');
    $left=$col->addColumn(2)->add('View_SlotMachine');
    $right=$col->addColumn(2)->add('View_SlotMachine');

 - Why the fields are duplicated ?
 - What does the method addColumn(2) does ?

Very thanks
