The amount of capital gain main residence exemption should only be reported at Item 18 in HandiTax:
Item 18, label M Capital gains in the Main form, Code I lets the Australian Taxation Office (ATO) know that you are reporting the Main residence exemption (Subdivision 118-B).
As this income is exempt, it should not be entered in the Capital Gains Worksheet.
If you have further queries on what data to enter at these items, contact the ATO.