Problem with Skeleton Mesh

Hello there !
I’m trying right now to make a robot ( all the animations , UV and modelisations are done ) except I did something I don’t know if this is bad or not :
My first animation ( the Idle ) , I made it on a mesh , no problem . I like to work with a space clean , so i exported this mesh ( with the idle animation ) to make an other one , and so on .
Except i modified a little bit the gizmos .
I’m trying now to link all these animations to make ma robot live , and it seems it doesn’t work whatever I try to do , is it normal ?