Thanks everyone...put him in it tonight and he went to slept better than he has in days...no crying or anything!!

I think that the fact that I transfered the same bed sheets from his cot that smells familiar, and that he had his 'cuddle shirt' (a shirt of mine), made him feel safe and secure. Also before dinner time, I put him in it and we played with his toys, perhaps made a difference.

Lets hope this continues when we go on holidays!