When you use the checkout wizard with Payments Standard the address override will be set to 1 so that it uses the address specified in the checkout form. There is no option within the wizard that will change this setting, if you need it to be set to 0 then you will need to update it after the fact.
I have logged this for eCart so that it can be reviewed. Here is also a link to the HTML Variables that PayPal works with in Payments Standard:
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