Hey Duane,
with Lee’s @TDE Fold Down Wall Mounted CNC Table you could try out different angles, including 45°, if you manage to retrofit a lock mechanism that is able to lock it at different angles. I’m sure this is possible. I can imagine that you might switch to other angles if you can experiment with it (including switching to 0° and to 90° one day) 
Also if your concern is that on 90° vertical (wall mount) position, the wood dust could fall downwards onto the ball screw, you could try to not mount it the way as shown here but with the Y axes vertically and X axis horizontally, so that any ball screws are out of the way of the dust falling downwards.