Sorry your post seems to have been overlooked. Is this a sliding type shower door or swings open? The sliding doors hang on the top track and have a nylon or plastic spacer the keeps the door aligned in the track & prevents it from swinging sideways in the track.
The swing-out doors I've installed used hex head screws to attach the hinges. If you take a look at the door hinge system you should be able to see it.
All you need is ignorance and confidence and success is assured. - Mark Twain