Sr Tamsin's first talk is available here: The Beatitudes as imitatio Christi. You can also listen to her talk on YouTube. Sr Tamsin's second talk was on The Beatitudes as an Examination of Conscience. The audio version is here. Sr Tamsin's third talk was on The Beatitudes as a Programme for Action. The audio version of that talk is available here. The fourth and final talk was on The Beatitudes as a Pattern for Prayer. The audio version with extra material is available here.