Crossworlds and Armored Princess

[deadguy]

I picked up both games pack as part of the Humble Bundle weakly sale, but I'm a little confused about Armored Princess and Crossworlds. Everywhere I look says Crossworlds is an expansion to Armored Princess, but it's over twice the size, and has to be downloaded separately instead of as add-on content. Do I beat Armored Princess first, then transfer my save over to Crossworlds? Or will they merge once I've downloaded both? Or does Crossworlds include Armored Princess in it, making Armored Princess nothing more than a waste of space on my computer? Is there any advantage to downloading Crossworlds before beating Armored Princess?