(wrote this up in the middle of the night, and then forgot to submit it ... it still might be of use, though).
I can't point you to that particular design, but I do know of one that might work:
It has a few design flaws**, but the way that the base unit is designed, there's four steel loops that don't actually meet in the middle. I suspect it would work well to keep the wok centered.
It has some disadvantages (it's larger and heavier, as it's a two-burner unit), but the extendable legs would bring it up to a more useful height for cooking on.
** and then the list of flaws that I noticed:
- The directions for the one that I got last year didn't match the parts in the box. (it was more assembled than the instructions suggested).
- The extendable legs flare out for stability, but they fold into the same plane. If you have the inner legs in there, then the legs won't fold flat. You'll either want to remove a set of legs for transport, or remove the plastic cap on the outer part of the leg so the inner leg can slide further in. Either one will slow you down when setting it up.
- The legs have a lock to hold them open, but not to hold them closed. (Most likely because as designed, you can't fold it all that flat without the modifications I've mentioned. I've thought about taking a dremel to mine to cut a notch so the pin will lock them when closed, but haven't done it yet).
- The central burner gives the griddle a huge hot spot in the middle, and a significantly cooler outside. Make sure to warm it up on lower heat, as high heat will make the griddle visibly deform (and the griddle is 1/8" steel)
- The griddle's just a bit too big to set into a standard oven (maybe at an angle, but that would make it difficult to season), so you'll have to season it using the burners ... but the uneven heat makes it difficult to season the edges without baking off the seasoning in the middle.
I haven't actually used the grill portion yet. I need to take a better look at it to see if the closed lid (which latches shut so you can carry it by the lid's handle) holds the cast iron grill grates down so they don't flop around when carrying. I also have no idea how well it cooks, or how well it deals with grease dripping.