I'll throw a couple of thoughts out for you:
If the paphs are under another level on a bench, you can attach a slightly sloped piece of rigid clear plastic under the bench to direct away the water draining from above.
I won't claim to know the physics behind it, but it appears that - when placed under glazing or shade - plants perceive that glazing to be the source of the light, meaning that varying distances from it can allow you to vary the light intensity. To help grasp that, consider this:
In my greenhouse, I have vandaceous plants hanging high, right under the glazing, so they get the most light intensity. My lower-light plants are on benches 6 feet away so they won't burn. If the glazing was not acting as the "light source", the difference in light intensity between 93-million miles from the sun and 93-million miles plus 6 feet would be insignificant.
Ray Barkalow, Orchid Iconoclast
Using science and logic to advance orchid growing
Treat Your Plants Right