The treks of days 4 and 5 are are marked on this map (right to left).

Day 4. We walked from the hotel in Pontresina for short while, and then travelled on horse carriages on land owned, we were told, by one Mr Rosteg all the way to the Rosteg's restaurant. From here we started a long trek to the Coaz Hutte, perched rather precariously on a cliff overlooking a glacier. By the time we returned to the good hotel Edelweiss in the next town, Sils Maria (lit. Lake Mary), it was 8:30pm.
Day 5. We trekked up to the third real summit of the trip - Piz Lenard (on the top left side on the map). The climb up was supposed to be more 'exposed' than the earlier ones, but didn't feel worse. Trekked down to the town of Maloja, and took a bus back to Sils Maria.
Day 6. I don't have the map for the trek we did on this day. We took a bus to the town of Casaccia, and trekked to a pass, Val de Cam. Then we did a long hike on to the lovely Roman village of Soglio. This was a pretty long trek; we made it back just before the restaurant took last orders for dinner at 9pm; can't recall what we ate, but much alcohol was consumed that night.
Day 7. On the final morning, we walked around Soglio, caught a late morning bus to St Moritz, and from there a train back to Zurich.