I found the installation instructions...link provided. I've never had nor seen one of these gizmos but, from reading the instructions, I think you can disassemble it in situ to diagnose your problem. Sounds like maybe the hub (bottom positioner assembly) has come unfastened from the shelf. If not, at the link, the drawing is labeled w/ part numbers so you should be able to get parts to repair. Won't be a fun job, but looks doable. Here is a link that might be useful: Installation Instructions

I had one in my old kitchen and it was the only cabinet that worked as well the day we demo'd as the day we moved in! It was installed in 1995 and we demo'd in 2008. Smooth operation, no issues with the shelves slipping or moving in any way. (Yes, it had a center pole.) I really liked the door attached to the shelves b/c there was no banging of doors or doors getting in the way. The door rotated in with the shelves and the entire opening was available for retrieving items (no hinges, etc). Both doors, from what I remember, were the same size. We never had any issues with it not staying "closed". I seem to recall there was a "stop" that kept it closed - part of the rotating hardware, I assume since there wasn't anything (that I remember) on the door or in the cabinet opening. The other thing I liked about it was that the walls of the cabinet very closely followed the contour of the shelves so there was no possibility of anything ever falling off. Jakuvall may be right about why some people hate them. In our case, we stored all our pots & pans in it along with colanders and several large serving pieces. It was nice having everything so accessible! I miss it! Note: Our cabinets were builder-grade, but the corner susan was definitely sturdy & well-made! Old Kitchen: (Yes, there is gap around the doors, but I think that may be b/c they were builder-grade and the quality tolerances were probably pretty wide! I would expect much better with a higher level cabinet or semi-custom or custom.)

Hafele generally makes cabinet hardware and fittings (think: a higher-end version of Rev-A-Shelf), not complete cabinets; they sell their wares mostly to cabinetmakers, so there may be several manufacturers with that same basic design. A closer look at the pictures show that the countertop surface doesn't appear to revolve, although it looks like it could be made to. That may be a good thing. Anyone who wants more info can check out the blog from someone who recently installed these and where I first saw them, and ask there.... Here is a link that might be useful: Cherry Hinton Blues

Other things to consider... If you must have filler, consider filler pullouts. Rev-A-Shelf, for example, has 3"/6"/9" base filler pullouts and 3"/6" upper filler pullouts. Consider deeper upper cabinets. Even an extra 1" can make a difference. Keep in mind that cabinets are measured based on overall measurements, that means the exterior measurements, not interior space. So, a 12" deep cabinet is really 12" on the outside. Once you factor in the thickness of the back wall, you now have only 11.25" to 11.5" interior depth. If you have framed, the interior depth is reduced again by the thickness of the frame. However, if you have overlay, you only lose depth due to the frame along the walls, the rest of the cabinet can use the frame space b/c the door sits in front of the cabinet. If you have inset cabinets, OTOH, you lose that space b/c the doors & drawer fronts sit inside the face frame, so those 12" deep cabinets are now down to 10.5" to 11" deep (depending on the thickness of your back wall & frame). So, a 12" diameter plate will not fit in a 12" deep upper cabinet. If you add an inch to the cabinet depth (13" deep), you now have that 1/2" to 3/4" back. 15" deep uppers are even better. If you have the space, consider deeper counters either with deeper base cabinets or by pulling the cabinets out from the wall a few inches. Staggered-height cabinets are personal preference, even with 8' ceilings. If you like them, get them. One thing to keep in mind, however, is that dust does accumulate on the tops of cabinets that are not to-the-ceiling. One way to make cleaning easier - line the tops with newspaper. When it's time to clean, just remove the newspaper with the dust that collected on top of it (and not on the cabinets themselves) and replace it with clean newspaper. If dust allergies or asthma are a concern, I recommend all cabs to the ceiling. Double-bin trash pullouts...love them!!! Dogs cannot open them! (Our dogs learned how to open the step-on ones in our old kitchen!) With two bins, one can be used for recyclables and the other for trash. However, put it in the Prep Zone...and, if possible, near the Cooking and Cleanup Zones. If you only have one sink, your Prep Zone will end up on the side of the sink closer to either the range/cooktop or refrigerator. So, put the trash pullout on that side. Put the DW on the other side...it will also keep the DW out of the Prep Zone (and the DW will not be an obstacle to work around while prepping.) Oh, and consider getting a foot pedal so you can open it hands-free. Keep in mind aisle widths should be measured counter edge-to-counter edge, not cabinet-to-cabinet. Strive for adequate aisle space, seating overhang, etc. Measure your space 3 or 4 times (or 5 or 6 or 7 or....)!! Measure from at least 3 different points vertically when measuring wall/space width...a foot or two off the floor, 4 or 5 feet off the...