In the design mode for the column control specify the format. Example as
[1] & then you can select 4 & 5 columns. More details explained at
http://www.sixdimensions.com/creating-a-column-control-in-adobe-cq/[1]2;cq-colctrl-lt0
2 Columns (50%, 50%)4;cq-colctrl-lt3 4 Columns (25%, 25%,25%,
25%)5;cq-colctrl-lt4 5 Columns (20%, 20%,20%, 20%,20%)