Trinity on a Mint base?

Something somewhat similar to the Kubuntu 14.04 problem - a few months ago I did a fresh install of Mint (Debian Mate) in order to have its wifi functionality. Then installed TDE base and several useful packages, which work. Later I installed TDM and other packages it seemed to need and chose TDM as the login mechanism. During login using TDM, the list of available sessions doesn't include TDE, and the subsequent desktop is still Mint. So maybe I missed some packages or configuration? Robert