QIf an enemy follower being put from the field into the cemetery has had its attack changed, does this follower's automatic ability deal damage to the enemy follower's leader equal to its new attack value?

AYes. The damage dealt equals the new attack value.

QDuring my turn, if 5 enemy followers are put from the field into the cemetery at the same time, how many times does this follower's automatic ability trigger?

AIt triggers 5 times.

QDuring my turn, if an enemy token follower is put from the field into the cemetery, does this follower's automatic ability trigger?

AYes, it does. The token is put into the cemetery, then it is immediately removed from the game.