All three products work with the PN user accounts; further integration has been done a number of ways, but those who do rarely document how they did it. phpBB2 is well supported, including at the style level.
Drop down selectible boxes can be done with some html modifications to the templates; extra fields are text by default.
Albums work regardless of integration.
A discount is applied to the purchase price at the time you all three products. I believe the discount is $10-$25 per additional product.
Please do not PM me for support or sales questions. Thank you for your understanding.