We built this in early 2013. We ended up turning the house 90 degrees on the deck, because the slide worked best off the backside of the deck due to the various heights around the deck.
The sloped back yard caused some challenges, but in the end it's a very sturdy deck with the cross beams attached.
Thanks for posting these plans online for us, our 3 daughters are loving the playhouse and swingset!
Here are some more pics of the project: