[Zope] Silva

I'm new in zope world. I would like to install Silva as a product in zope. When I put all core silva product to lib/python/Products cataloge unpack it an restart zope again every think seems to be good but when I want to do next step from INSALL.txt of Silva namely on "add list" of ZMI I choose Slva root and want to add it to zope root folder after I feed Id and Title on the "Add Silva Root" page and I push "Add" button I receive "HTTP 500 - Inside Error of server Internet Explorer". Where is an reason of this error? Any hints?