Hi, about packt pub’s book, dont know if anyone else discovered this, but I examined the platform model and one of the planks normals are inverted !! so thats why it was popping through!! I dont know how to flip normals yet, but replaced faulty plank with copy of other one and it works!! Just sharing quick tip guys 
Thanks, I never noticed that happening for me but maybe it’s there and I just didn’t notice.
How are you liking the tutorial? I found it pretty cool and learned a lot about unity.
The book is great !! I wouldnt have had a clue without it. Im trying to solve another problem now about the door not fully closing all the time. I imported my own asset from Maya, but that also doesnt completely finish the close animation!! grrr. Ill make new post if i find solution