I use the 23CII and my lensboard is held in place with a spring piece on the back side. Slide the lens board back against the spring clip and push back while raising the front of the lens board. It snaps into place and won't come out unless you push the board back and pull down on the front of the lens board. Sounds like yours has been modified.
The lower bellows is held in place with screws under the neg. stage plate. Thats the way mine is attached.
I'm not sure if I would try to make the bellows more pliable. Someone else might want to answer that one.