Honestly, I wont recommend anyone to stay in the 'old town' during your visit. I think Marrakech is a dangerous place to go by your own, unless you have a group of 5+. It might be OK.
Fortunately, I found this peaceful raid online, my hubby and I like this Riad a lot. It is the only comfortable and safe place in this 'maze' (old town).
In the first night, we stayed in a small old room, which isn't comfortable at all. The room was cold and smelly. So, we requested for a change of room. The manager was very helpful, he checked the vacancy, and immediate swapped the room for us. We were so impressed.
The riad offered lovely continental breakfast, I really enjoy the fresh orange juice everyday. The places outside the riad is a chaos, so, my hubby and I preferred to come back earlier and enjoyed our drinks and snack here. The atmosphere in the raid is romantic and with detailed Moroccan decorations. We love it!!
I would recommend Riad Karmela to all of you if you really want to stay in the old town.