Procedures that require file editing on the Management machine are not directly supported in Smart-1 Cloud. Such cases should indeed go through TAC and they will make the change & document it so that we can take it into account when maintaining the environment.
We understand that this may cause inconvenience to customers / partners that are used to doing this independently, therefore we are looking into ways to improve. One direction is to give restricted access to upload specific files, and another direction is to enhance & streamline the .def editing mechanism to the benefit of all customers (not just in Smart-1 Cloud).