I am trying to pivot an mdx query and am running into syntax errors,
or what I am trying to accomplish cannot be done. Any help would be
greatly appreciated. Here is the query:

WITH
MEMBER [CustomWellGroups].[Office] AS '[CustomWellGroups].[Office
Name].[BAIROIL OFFICE] + [CustomWellGroups].[Office Name].[ANSHUTZ
OFFICE]'

SELECT
CrossJoin({LastPeriods(12,
[ActivityDate].[2004].[Feb])},{AddCalculatedMembers([Measures].members)})
ON COLUMNS,
{[CustomWellGroups].[Office].Children} ON ROWS

FROM
POS_Activity_GrossExpense

WHERE
([GER_COAGroup].[Gross Lease Operating Expense].[880 : LEASE
OPERATING EXPENSE].[880.18 : COMPRESSION EXPENSE])


When processed this query returns the following error:

"Unable to display opened cellset
Cells cannot be created for this cellset because on of the axes
contains no positions."

When using the defined member as criteria in the WHERE clause this
works fine, but trying to access the children of the defined member
for the rows it seems this information is not available? If the
..Children part is removed information is returned, but we need the
children...

Once again, any information that explains what is wrong or the flaw in
the logic would be greatly appreciated.