[Zope] Effective Rights

Hi. Is there any way to calculate a roles effective rights on a object in Zope? I currently have the situation that I can access two DTML documents in a folder anonymously, and two other DTML documents only with manage users. Trying to track the problem down, but I dont get it right. What about this acquire permission settings checkbox? Is there any special behavior when I added a local role in a folder? Can this affect acquisition of permissions of e.g. the anonymous role? CYa, Mario