general problems of the 2008 Dodge Caravan

Incident we took our 2008 Dodge Caravan it in a month ago one of the problems we were having was the driver side rear sliding door wasn't closing properly so we had them adjust it. We took it in a month later to fix other problems and the door they adjusted on the drivers side just fell off in my driveway and I am again without an automobile. The van door works in two ways. One, you can push a button and close the door, or two, you can click the inside handle and slide the door over until the motor grabs it and closes it. The way the door is mounted in the rear track is very inadequate. There are two small horizontal load runners and one vertical load runner. The track is made from steel but when adjusted improperly can be stretched out of shape. When the front door lock is engaged and the rear lock is engaged the rear track can get pull out of shape and the wheels on the slide can fall out. I am an engineer who works constantly with the equipment that builds these vehicles in the auto plants. I design machines that could cycle a million times. This is an inadequate design.