Hi Ralph
I think you've fallen foul of a bug that inserted a single <space> character for tasks without a Dependency, causing the app to think it has a dependency but it not appearing to have one in the edit field.
If I'm correct then displaying the 'Dependency' column will show an icon for that task.
I believe from memory that clicking in the Dependency field and hitting the space bar should be enough to reset the attribute and fix the problem.
If this does not work then you will need to send me the tasklist because it sounds like something new...