I was wrong - it doesn't work just by changing it to a 3.
Did anyone ever manage to get this working with 3 colums of links? It all seems to work ok until...
<%if row_num % 3 eq 2 %> <%-- balance the trailing rows --%>
at which point it goes haywire. The code doesn't seem to be sure how many empty or fill in colums it's supposed to be building.