To make sure that the redirection of all trackable links in your e-mails works, you have to define the base URL for the OpenEMM redirect service in database table "company_tbl" in field "rdir_domain". Please do not forget a leading "http://" or "https://" which is required by the OpenEMM redirect service.
During installation you can define the base URL by replacing the default URL "http://rdir.de" in file openemm.sql which is used to fill the database with initial data.