If you want to display variable number of columns in the report I suggest you use a matrix element.
To utilise it for this you need to flatten the result of your query. The query can be changed into something like this:
select
{ [Utility Dimension].[Value].[Current] } on columns,
{ CrossJoin( {[TimeByMinute].[All TimeByMinute].[2005].[May].[1] : [TimeByMinute].[All TimeByMinute].[2005].[May].[6]},
{A_list_of_measures }) } on Rows
from ACD_Calls
This will effectively return a set with columns for your date, a column with measure name and a column with the actual value for the cross-section of the measure and the date. Utility dimension in this case is an auxiliary dimension with just one member [Current].
If you don't want to create a Utility dimension you can use an existing dimension's (that isn't included in the CrossJoin) [All] member instead.
Hope this helps