Definately cover the crate it will make him feel more secure, leave a radio on too that sometimes helps (put a talk or classical station on low)

Try and distract the initial leaving with a stuffed kong or hide chew if he has them and create a little bedtime ritual. Dogs like routine so maybe out for wee, get treat,switch on radio, pop dog and treat in crate and night night.

It took Oscar 3 nights to work out that crying was not the way forward.

Good Luck.