It did have a piece of paneling and a ~1" foam cushion originally. They folded up inside the cabinet then, but then the it was basically useless in cabinet mode because it would be full. The 1" cushion was covered in fabric and was actually two pieces with fabric acting as a hinge, so the cushion would fold up in half size to fit in the cabinet. The paneling is key though because those cabinet door latches can't hold much weight at all, they break easily, so you don't want the cushion falling through to put pressure on that door. Also, all cabinet bunks have a 100# maximum weight.

Yeah, I figured as much that can not hold much weight. The one over the dining area look weakened and damaged in other areas. You could just push on it with your finger and see the give on was just too easy right in the middle. I think I will still put paneling or a sheet of wood for extra support even for whatever get stored in the cabinet space. If I ever decide to use it as bunk. I would add support beams (round steel poles like for a fence or bar table) underneath on both ends (two on each).