I have a project where some headline milestones are listed at the top, and are dependent on tasks completed at the bottom of the schedule. Even that the dependencies are simple and clearly not circular, I keep getting “circular dependency” warnings; I suspect the order of the entries may incorrectly be considered in the logic for the test.
That is always frustrating…. it can be difficult on large projects to detect ‘where’ the circular logic/dependency is…. One note: it is Best Practice not to have a Summary task linked but to inherrit properites from the sub tasks. Maybe try that so it is more clear.