It took me a while looking at the instructions to figure out if the deck on this model is supposed to be planked. I’m accustomed to planking a deck that’s free of obstructions, and the pre-molded deck and deck houses seemed like they would be awkward to plank around. Also, the illustrations in the instructions don’t seem to show any indication that you are expected to plank the deck, though the photocopy-quality photos do show a wooden deck. But, the question is answered in a short paragraph in the instruction text, that clearly states that the deck is to be planked. Also, there are sufficient light-colored wood strips for deck planking.
Now, I’ve seen photos of models by people who have laid deck planking right down onto the plastic deck. But if you don’t want to deal with trying to fit the planks in between the deckhouses and such, you might try what I did.
I started by making a copy of the deckplan. Turned out to be pretty close to the molded piece. I cut out the deck and openings for the deckhouses and test fit on the model. It took a little extra trimming around the deck houses.