If anyone wants to test the development version i have added the following :
In the Donate Extra Admin section it now shows the gross and net amount for each donation and at the bottom the gross total and net total .
P.S. The settings for the PayPal percentage and PayPal fee have not yet been added to the Setting sections so if you do use the development version you will have to adjust the following variables to suit your countries PayPal fees in the file manage-dp.php
// Set Fee Rate Variables
$fee_percent = '3.4'; // Paypal's percentage rate per transaction (3.4% in UK)
$fee_cash = '0.20'; // Paypal's set cash amount per transaction (£0.20 in UK)
Hopefully soon you will be able to change these values from the Setting page.