If you use No VAT then it will gross up the transaction which will be wrong.  I agree it will not fully be 20% of the VAT in boxes 1 & 4 due to reverse charge, exempt purchases etc.  However, if I post transactions to add or subtract these where will the double entry be as I do not want a creditor or debtor balance then showing on my ledger.    It does seem bazaar that you can adjust part of it but not all of it like you can in Sage for example.......