I have to say NiftyChick, that we built the Playhouse Coop, and it is really perfect for the small backyard chicken owner! It provides a safe, elevated house, and a secure run that is perfect for 5 standards or 10 bantams.
The changes we made were to
1. Modify the house to a 4'x4' (instead of 2'x4'), which makes a huge difference.
2. Since it was bigger we added two 2x2 roosts (we have bantams-- but it could easily accommodate 2x4 roosts)
3. Placed wire on the bottom and then covered it with 6-8 inches of hay, to make it completely predator proof.
4. A heavy duty magnetic closure on the bottom corner of the door to prevent predators from getting in.
Other changes we now wish it had/I would recommend for a future plan:
1. It could also be made MUCH SIMPLER and cheaper by doing an angled roof instead of pitched. (Although I love the look of the pitched roof!)
2. It desperately needs some kind of a clean out access door somewhere! As it is, I will have to get a rake and scrape out the shavings through the chicken door at the top of the ladder! Good thing we do deep litter and are planning on changes only a few times a year!
3. This coop was built for harsh winters relying on the small house and chicken body heat to keep it warm without additional insulation. I don't know how this changes that, since the house is now 4x4. There is also no ventilation, other than a 1/2" gap where the hinges are for the fold down door. This works perfectly for us where during the day it gets to mid 90's in the summer but at night drops to the 50's. I would assume that in climates where it was still very hot at night (or super cold in the winter so they are locked in the coop for months) that they would need substantially more ventilation. Since they are in the run during the day, but the coop at night, this has not been an issue for us.
That's it!!
I think that if these plans were modified as extensively as I have suggested, they would not at all infringe on the original designers work, as there would be a substantially different coop created.
Hope that helps!