Can a simulacrum be healed by any means other the ‘complex process’ outlined in the spell?

Inspired by another discussion of Simulacra – can a simulacrum actually heal via any method other than the ‘complex process’ outlined in the spell? Or is that process simply another option? What if the copied creature type has Fast Healing, or Regeneration? Do Cure Wounds spells function on the simulacra? Is the simulacrum actually even a creature?