You insert the guestbok object where you want it on your site(s), click on content og dobelclick to insert the options you want for it. No, you don't need to have a database for it. In the option "Data save settings" you just pick "send data to file" and in settings you can call it for exampel "Guestbook" og what you want. This is for the choise "Website x5", but you can also juse Facebook og disqus if you prefer that. None of them need databas, but you need an acount.