Hi Ian,
My expereinces with this orchid have been that it requires a good amount of water and humidity when in active growth. When I failed to provide it enough water the pbulbs got really wrinkled. In addition, all the new growth came in stuck together and twisted.
The seller who provided me instructions on this orchid mentioned the need for lots of water during the growing stages but I was afraid of rotting the roots.
I have since switched it's potting medium to coconut chips,shredded husk mixed and fine (light) pea gravel. The medium dries quickly, and I can water and mist it often.
The older pbulbs never really recovered from the damage I did them. However, the new pbulbs are very pretty