Adding code for source systen in bex analyzer workbook

Hi,

I have below code written to display source system of queries in WAD script.

/************************************************************************************************************
* Change the content of Text Web Item "SYSTEM1"    *
************************************************************************************************************/
function executeCHANGESYSTEM1( currentState, defaultCommandSequence ){

var originaltext = document.getElementById('SYSTEM1_TextItem').innerHTML;
var textoutput;
var systemabbr;
var firstport = "FirstPort";
var hrcore = "HR Core";

// Use only first 2 characters of the Query name
systemabbr = originaltext.substring(0,2);

// Determine wether the Query name starts with "HR" or "FP" and replace with according system name
if ( systemabbr == 'HR')  {
  textoutput = hrcore;
} else if( systemabbr == 'FP')  {
  textoutput = firstport;
} else {
  textoutput = firstport;
}

I want a similar code to be written in Bex analyzer to display source system. I think it should be wriiten in VBA. But when I press alt+f11, many screens open up. I have never worked on VBA. Can you please help to let me know where to write such code.