Delete payment_authorize.zip file from payment folder administrator/components/com_virtuemart/classes/payment/payment_authorize.zip
I answer to this post just to assure you i am taking notes of all these little issues you are posting and i will fix them in these next couple of days.
Thank you again for your very good testing work.
But... regarding this post... you sure it doesn't come from a previous VM 1.5 test install? I have no such file in SVN.
Maybe it is a left over, thank you for checking.