If you have not heard back from the hotel by email, write to them again and make sure you include your full name, dates that you want a room, that your on a RS tour, starting date of the tour for hotel that is prior to the tour, end date of the tour if this is the hotel for the end of the tour you need a room for, and ask how much is the room and that you would prefer to be in that room during the whole stay prior to the tour and during the tour, and the start of the tour ( so that you do not have to move rooms). If within a two day period you do not hear back from the hotel, call them. This is what I do to insure I get a room with the hotel. Ask them if you need to pay in advance and if so would a credit card secure the room.
If you are traveling solo, tell them that and that you will be in the room alone during the whole stay. If you have a roommate, then you will have a single room before and after the tour, but will be rooming with someone during the tour, then, you will most likely have to move rooms.
I hope this helps.