OK... well this is very odd...
I don't see how this would be processed by paypal at all?
The key part of the dump is:
["PP_DirectPayment"]=> string(2087) "AFcWxV21C7fd0v3bYYYRCpSSRl31A3tt82011-01-05T20:46:04ZFailured88e1f096baf8Security errorSecurity header is not valid10002Error2.201620725"
Which is not a Success with Errors, but a straight failure, and "Security header is not valid" means that the username, password, or security key that you have entered is incorrect.