Auditing Inserts with Identity columns

G'day Robert, 
The Audit table is defined as an Entity in our EDMX, but does not have a FKey back to the source table... we have a single audit table for the entire schema, storing the related entity name (GetType().Name) and ID as a non-related int.

Our save interceptor currently looks as follows:

/// <summary>

    /// This class is hooked into the Save pipeline to allow us to audit changes to data.

    /// </summary>

    public class AuditingSaveInterceptor : EntityServerSaveInterceptor

    {

        protected override bool ExecuteSave()

        {

            var entitiesBeingAdded = EntityManager.FindEntities(EntityState.Added).OfType<Entity>().ToList(); //get a concrete list, not a queryable.

            var entitiesBeingUpdated = EntityManager.FindEntities(EntityState.Modified).OfType<Entity>().ToList();

            AuditUpdates(entitiesBeingUpdated);

            var entitiesBeingDeleted = EntityManager.FindEntities(EntityState.Deleted).OfType<Entity>().ToList();

            AuditDeletes(entitiesBeingDeleted);

            if (!base.ExecuteSave())

            {
                return false; //don't go any further if that bit of work failed.

            }

            //TODO: Audit inserts later on.  See http://www.ideablade.com/forum/forum_posts.asp?TID=2717&PID=10825#10825

            //AuditInserts(entitiesBeingAdded); 

            // return base.ExecuteSave(); //doesn't save the new Added audit records, attempts to re-save the items saved above.\

            return true;

        }

        private void AuditDeletes(IEnumerable<Entity> entitiesBeingUpdated)

        {
            AuditChanges(entitiesBeingUpdated, "Delete");

        }

        private void AuditUpdates(IEnumerable<Entity> entitiesBeingUpdated)

        {
            AuditChanges(entitiesBeingUpdated, "Edit");

        }

        private void AuditInserts(IEnumerable<Entity> entitiesBeingAdded)

        {
            AuditChanges(entitiesBeingAdded, "Add");

        }

        private void AuditChanges(IEnumerable<Entity> entitiesBeingUpdated, string auditType)

        {
            if (Principal == null || Principal.Identity.AuthenticationType == "Anonymous")

            {
                // we can't audit this without a proper ID to record it against

                Debug.Assert(false, "DANGER: Not recording audit information as there's no authentication information available.");

                return;

            }

            var userId = ((HCareIdentity) Principal.Identity).UserID;

            foreach (var entity in entitiesBeingUpdated)

            {
                var audit = EntityManager.CreateEntity<Audit>();

                audit.EntityAspect.AddToManager();

                audit.AuditTime = DateTime.Now;

                audit.AuditType = auditType;
                audit.EntityName = entity.GetType().Name;
                audit.EntityID = (long)entity.GetType().GetProperty("ID").GetValue(entity, null); // All our tables have a "ID" column storing the identity value.

                audit.ChangeByID = userId;
            }
        }
    }