How to extend the limit of members for a filter on Demantra Worksheet?

We are trying to create a worksheet to meet user requirement to display data for all customer accounts except for two customer accounts (which are the two largest accounts).  When defining the filters, we receive a warning 'You can not select more than 250 members for the filter'.  We cannot use any other hierarchy levels to meet this requirement.  Isn't there a system parameter that can be set to extend this limit?  We are on Demantra 7.2.0.2.

Any help is appreciated.  Thanks