thanks for all your comments!
Answers to some questions:
*other preparation walks: we had taken Flora on a very simple small camping trip when she was just 6 weeks old. close to home, only 3 hour walk, to test the sleeping in tent experience. It rained a lot that night but part from 1 single shout at 4 AM she slept fine that night. We tested the combination of a mousse pad with flora on top and around all of it our fleece, whch worked at that age. We did many more daywalks before leaving and had two weekends in a house, where we improved the sleeping construction, but part from that: nothing else.
*the other nights: usually fine up to 5 or 5:30 AM. As she has the habiit of waking u for first time then, we used that opportunity to get up and leave, she would be tired by the time we left, 30 minutes later, and sleep on in the sling for at least another hour. We had our breakfast while walking. I can't recall any other really bad night, although she did ask for a drink some times, as she also does even now at home, at 8 months almost
*as for the sling and the backpains: not really, no. Once you know how to use the sling, there's no real strain on the back worth mentionning. Sometimes, when the sling is not properly attached, the shoulders did feel some tension, especially when I carried her and then my backpack over the sling. For the combination with a real backpack, there must indeed be a way to make the combination a little more comfortable. Which makes me think: on with the mission for the DIYS backpackers here!