Format_string in icCube does not format null values

I was trying to display values ​​that are 0 using format_string.

I currently have the following:

WITH 
    MEMBER [test] AS null, FORMAT_STRING = '0.#;Neg (0.#);0.00;0.00'
SELECT
[test] ON COLUMNS
 FROM [Sales]

      

        
        
        
      

    

The fourth value (; 0.00) should format zeros to zeros. I read this here: https://msdn.microsoft.com/en-us/library/ms146084.aspx

It is currently showing nothing. It should show 0.00.

You can try it here: http://www.iccube.com/run-mdx