Trigger email notification using business rules

Dear All,

We are working on Hyperion planning implementation and planning workflow process is not fitting the client requirements as we are using self-approval system (single user will review budget and approve-only email notification will go to budget owner). Would like to know if we can trigger email notification using business rules once the user completes his task list.

We would like to stop the approval process if validation fails in data forms. But using workflow process its not possible. Hyperion provides "Do not promote" option but it works with minimum two level review process. As we are using self approval process its not working as expected.