you can use a red bulb as long as it is an infrared bulb. pretty much any red bulb you get at a petstore should be infrared. (snakes can't see infrared light, so it doesn't disturb them).

any color hide is fine as long as it is opaque. if it is see-through your snake won't feel secure in it.

you might try cypress mulch bedding--it holds humidity much better than aspen. you will have to mist according to the humidity level with the adjustments that you have made to your setup. your humidity should be at about 60%.