IOr as it’s speculated, it was completely impulsive to take MM and this is a one off crime which resulted in her murder.
He could have attempted burglary but kill the child accidentally and then take her with him out of panic, this is not impossible.
Another thing is that he might have had an accomplice to either the burglary or the kidnap.
He and the accomplice could have as well fallen out during the burglary/kidnap or something could have gone wrong.
The very interesting thing is that nothing had been taken from the apartment apart from Madeleine, this could as well be intentional.
The other options are: that he took her only for making videos, or only for himself, premeditated or on impulse.
Then he could have taken her to order. Or change his mind and not pass her on. Or take her for himself and then pass her on. She could as well be alive somewhere.
Now, I have been thinking about this for days, more I read about CB more I think Madeline was taken to order. If it was him. He could as well have been only the accomplice, like provide transport etc. as he usually does.
I wonder what happened to the removable roof of his van, and whether it was still there when police checked it.
We have lots of info about CB, sometimes our inner logic works the best.
If we close our eyes and let our minds try solving this puzzle ( this is what I sometimes do with mathematical tasks) then the most logical solution appears.