(hope that worked!) It would be placed in the middle and the dog only has to nudge the end with its mouth to get it to spin round which as it does releases treats so dog always ends up with one 'arm' of the puzzle in front of it full of treats. Ideal if you feed kibble for breakfast and just want to add a few tasty tidbits such as bits of cocktail sausage or cheese.
If you feed some more like the applaws flaked chicken or fish mixed in with kibble maybe a Slo-bowl?
The reason I thought bean cube might work better than a childs table or something is because of the angle of the front wheels on the quad cart.
The cube should fit between them and can maybe remove the chin bar if necessary (if dog is only standing) so it can reach the puzzle or food bowl in front of it.
I think wet food maybe easier in a kong or starpod etc and fed with them laid down so they can empty it properly same for chews or bones.
On sunny days my old girl loves to lie in the ball pool pit in the garden and I scatter treats in it hidden under all the balls she can lie in it (without the cart).
The Trixie Turnaround can be played with dog laid down too.
Any other toys/puzzles that could be played different ways for dogs with limited ability to chase or move round a toy?
So basically you are looking at getting her to eat slowly so she will be standing longer but with something interesting to do. I see what you mean, my dogs usually have their food gone in about 1 minute. 
She would probably love the ideas. At the same time, if you put her in the cart she will be standing with or without snacks or anything like that, but it would be more interesting this way. Eating will be good for getting her to weight shift forward, which she would naturally be doing if she is weak in the rear. Maybe you could also make a kibble trail for her to slowly follow and munch. If you do it on an indoor surface or cement, she might be able to go by herself one step at a time, or if she needs help it is only a lot of very small pushes for you as she progresses following her kibbles. Another idea would be to hide strong smelling kibbles around the room, under a towel or behind things and let her work at getting them out, kind of like an Easter egg hunt. I remember Sheri put a string on Pete's bowl and pulled it to get him to walk. 
Can you get them back? They would be good examples for other people who come along to search for ideas. If you upload them using the Upload Attachment link at the bottom of the compose screen, they will be permanent.
