Dynamic Column Selection not working

[ashishp]

Hi There 

I am using dynamic column selections. Upon selection of column name , column is getting added into Straight table. 

How ever I am able to add only 1-2 columns at a time, when trying to add multiple columns its not working. 

I am using following expression for "Show Column If" condition. 

if(SubStringCount(GetFieldSelections([Dim Selections]),'Billing Effective Date')=1,1,0)

Please find attached sample app for your reference. 

[ashishp]

Any suggestions?