@einstein
I think your problem with currency different from dollars is in the file tpl-top-confirm.php
Infact the $_POST['payment_gross'] should be replaced by $_POST['mc_gross'] !!
$_POST['payment_gross'] is deprecated field for Paypal.
YES! It works now!
1. I changed 'payment_gross' to 'mc_gross' in tpl-top-confirm.php (im all my themes)
2. I changed my modified theme to original theme - buy one highlight ad in dashboard and back to my theme again.
3. Now I can buy a highlight and top ads in my dashboard
Thank you very much einstein!