Report designer limits

I have some problems inserting queries into the report designer.

It seems only queries containing only key figures in the columns can be added as data provider.

If I have a characteristic in the columns I get a message: "Report Designer does not support this query drilldown. Do you really want to delete this section ? and at least one Characteristic in Rows!". (I also have characteristics in the rows. )

When I remove the characteristic from the columns, it works.

Is my assumption correct or am I missing something ?