Sadly there is no sqf command to change the row and column count on the fly via sqf which makes this control type very static even though it has some destinct advantages compared to lists and combo box controls.
Perhaps one of the following commands could be extended to also work with toolbox controls
//Setter
https://community.bistudio.com/wiki/lnbAddColumn
https://community.bistudio.com/wiki/lnbAddArray
https://community.bistudio.com/wiki/lnbAddRow