I was just looking at a floor plan. Could you sleep so that your head is at the foot of the bed, and then put the CPAP down there (or on some sort of stand so you can turn it on/off easily?
Or how about modify the cabinet above so that one can go there? and the other infront of the bathroom wall.
We have a popup, and since we are not particularly tall, we sleep so our feet are facing into the trailer. (So, no one has to climb over the other). When he started using the CPAP, he put a rubbermaid box at the foot of the bed (in which he stores his cloths) and when he is sleeping, the CPAP goes on top, and then he has an extra long tube. I really like this set up - since it is quieter than at home, because the machine is that much farther away.