The Redirect will be based on the $WAGLOBAL_Root_URL setting in the WA_Globals file.
The page paypal will use for the redirect will be:
$WAGLOBAL_Root_URL + pp_confirm.php
so if you set $WAGLOBAL_Root_URL to:
$WAGLOBAL_Root_URL = "http://mysite.com/"
paypal will redirect to:
if paypal is redirecting to a page that does no exist, double check that you have configured the $WAGLOBAL_Root_URL correctly.
you do not need to change:
to change to usseing euro, you only need to change this line in that code:
$WA_PP_ECO_Set_params[$nextIndex] = "Currency";
$WA_PP_ECO_Set_params[$nextIndex] = "USD";