Workaround for now...
IF [Rank] >= 1 AND [Rank] <= [Parameters].[Top X] THEN " " ELSE "Other" END
Leave the Top group blank, and have ELSE as Other.
Then the sort is always fine, but its not ideal, I'm still looking for a proper solution
Thanks John, Interesting way to tackle it...
Of the 2, I prefer the first.
The 2nd I can do as mentioned in various different ways (dont label the top, only the bottom, or add X/Z or something to the bottom group)
The only thing, can I keep it as is and still display the Rank?
Thanks for your help