Replace this
Code:
{if $reminder_display_not_completed}
with this
Code:
{if $reminder_display_not_completed && $SCRIPT_NAME != "/usercheckout.php" && $SCRIPT_NAME != "/thanks.php"}
Keep in mind that the operator $reminder_display_not_completed that I used in this example could be any one of the 3 possibilities that we provided with this mod, so basically just take whatever ones you are currently checking for and add
&& $SCRIPT_NAME != "/usercheckout.php" && $SCRIPT_NAME != "/thanks.php" to the end of them.