ScummVM RTG works (sorta)

The back plate is rattling because it is not tall and wide enough to fit the grooves in the top and bottom parts of the case. I don't know if it is on purpose because of the case moulding variations / orangepi+daughter board placement variations or who knows why. I personally installed passive dual side heatsink and made a custom back side metal grill so the hot air can escape. If you need any help regarding modeling or making custom parts, let me know. CAD/CAM is what I do. I would consider helping you design what you need for free.

Sounds interesting. What does your A600GS custom back plate look like?

That's a great idea, I might do the same.

If you mean the weights idea here is one cheap and easy solution. Go to hardware store and buy two galvanised steel perforated plates 80x40x2mm. Two of them give perfect weight increase to A600GS, they fit in the middle of the bottom part of the case and they won't rust. Then isolate them with electrical tape or put some isolator between the bottom of the daughter board and those plates. The plates are easily fixed to the bottom of the case with a glue gun and can be easily removed without any damage. 15 minutes of work

Good luck

I think the case is "ok" ... I did some rework with tape to prevent the metal plates from rumbling around and hold the audio jack in place ...

I already started to design a case with integrated 3,5" Floppy drive but it´s far from complete 

I think A600GS case is very well designed, very well molded, quality plastic etc. I would not change it I just made some modifications and I installed two 2mm insulated metal plates to act as weights underneath the daughter board and now is very stable on the desk and cable movement does not move the device anymore.
 

The back plate is rattling because it is not tall and wide enough to fit the grooves in the top and bottom parts of the case. I don't know if it is on purpose because of the case moulding variations / orangepi+daughter board placement variations or who knows why. I personally installed passive dual side heatsink and made a custom back side metal grill so the hot air can escape. If you need any help regarding modeling or making custom parts, let me know. CAD/CAM is what I do. I would consider helping you design what you need for free.