Seeking info on Bolin Visual Presenters (Document Cameras)

One of the schools I work at has 3 brand-new out-of-the box Bolin BL-2800 Visual Presenters. I haven't been able to find much information by users online and they are obviously not one of the well-known brands.  The documentation that came in the box is real skimpy (not even a diagram showing how to hook one up to a projector).  Worse than that, I can't get any of the buttons to function.  An image does get sent to the projector but nothing else functions (e.g. can't zoom. Can't even turn the lights on and off).  Does anyone have any experience with this brand and this particular make of visual presenter?