Remove columns with zero sum values in a matrix (P&L)

MVCPA 

Not sure if this will work but give it a try.  You are using 
RETURN Result

There is a trick with DIVIDE where, when you divide by 0 it returns a null instead of a 0 so you can use

Return DIVIDE(Result,Result) * Result

null * 0 is null

The whole measure would look like this.

Actual = Var Calctype = SELECTEDVALUE('Header Assignment'[CalcType])
            Var Displaydetailcode = SELECTEDVALUE('Header Assignment'[Detail])
            Var IsSubheaderVisible = ISFILTERED('Accounts Name2'[Account Name])
            Var IsBracketVisible = ISFILTERED(Bracket[Bracket])
            Var IsPeriodVisible = ISFILTERED('Date Table'[Year Month])
            Var Result = SWITCH(TRUE(),
                isSubheaderVisible=True() && DisplayDetailCode = 0  ,BLANK(),
                isSubheaderVisible=True() && IsBracketVisible =TRUE() && DisplayDetailCode = 0  ,BLANK(),
                IsBracketVisible =TRUE() && DisplayDetailCode = 0  ,BLANK(),
                    Calctype = 1, [SUM AMOUNT],
                    Calctype = 2, [Running Total A],
                    Calctype = 3, DIVIDE([Running Total A],[Rev amount 2],0)
                )
            Return DIVIDE(Result,Result) * Result