Many years ago I was in Gunung Mulu, at the Royal Mulu Resort: wonderful resort and impressive pristine jungle all around.
But it was rainy season, and I had too little experience with tropical snakes: the best thing would have been to walk during night rain along the road between resort, airport and park. Which unfortunately I didn't!
But in the following morning(s) I could see two huge Bungarus dead on the road: B.fasciatus (very big specimen, rather round and not triangular in section) and B.flaviceps. Considering the low traffic impact during night on that road, I think snake presence during those night rainy storms should have been massive.
On the intersection with park road, was spotted more than once a huge king cobra by the manager of the resort and his wife: but I could not see anything.
Other snakes I found were probably one or two Dendrelaphis sp. DOR (? I should search the pictures) and two specimens of O.taeniurus grabowski inside the deer cave.
http://www.ratsnakes.com/images/Etgrabowskyi.jpg