The issue is that for "down then across", the page length delimits the columns. If you have a fairly standard number of values from group to group, one way of handling this is to insert a subreport with the "can grow" on the subreport object removed. You then resize the subreport to force the number of values per column. The potential limitation is that you could cut off values if you don't make the sub quite large enough.
-LB