How do I choose required fields when integrating MarketPress with PayPal PayFlow?

Hi,

We’re trying to figure out how to customize which fields the user is required to submit to our payment sign-up form (which is driven by MarketPress and PayPal PayFlow in combination).

Here’s the kicker: while it’s trivial to set the required fields when you’re using a hosted PayPal form (i.e. you can just adjust this through the manager.paypal.com portal), it turns out to be a lot more nonobvious when you are NOT using hosted forms (as we are not).

Is there some trick to doing this in MarketPress? Nothing obvious about this is in the documentation, from what we can tell…

Thanks for your help with this!