creating a 1.5x template

I have a developer friend that said he would try turning a PSD into opencart theme for me but I wanted to get him as much info as possible, but I can only find the 1.4 template design cookbook, I know all the templates had to be redone for 1.5 so just wondered if anyone knew where I could get some information either instead of or in conjuction with the exsisting book.

thanks.

He could just download opencart and check out the template structure