I always thought that if a dog suffers from separation anxiety the worst thing you could do is to crate it. My sister-in-laws dog had SA and he would freak out when crated. He loved to sleep in his open crate, just don't close the door or watch out! We use a baby gate to keep our dogs confined to the kitchen while we are gone. The kitchen is big enough to where they don't feel too confined, yet they don't have access to the whole house either.

Often leaving a TV or radio on while you're away helps too.