[Zope] developer docs

What are the best documents for creating Zope products? I know Zope Book very well and I write TTW scripts. I need to convert a bunch of ZClasses into Products. ZDG seems very outdated. Should I start with mxmEasyProduct and then read ZDG? Is there a book available in bookshops that is better than ZDG and contains all required information for building products? -- Milos Prudek