This feature is only used if you have implemented the SAP Concurrent Employment model (for Global Employment).The system then allows you to send an employee on an assignment to a an affiliate company in the host country, and temporarily exit him in the home country. At the end of the assignment you repatriate him. Hence this feature informs the system which actions are related to Global Employment activities.Otherwise it has no effect on your system.
Basically ACTCE feature recognizes the action if you are trying to perform any action on the person who already exist in your system and have valid actions.