oh and i recommend not using an animation,
but to move the train via "ext_config.ini" using the railroad as mesh for moving the train
[ANIMATED_...]
MOVE_ALONG=rail_raod_mesh..
thank you so much for your answer

but i think i explain the wrong way my problem ( i m french so my english sucks...)
my problem is to export an animation in kseditor without deforming or any troubles...
i use blender and a mixamo animation ( all fine in blender ) but when i export the character with mixamo animation in kseditor ...bimmm troubles...all mesh is breaking !!
i think it's a problem with location or scale or something , because when i export in the location of the center of blender no problems at all ... but i don't want my character in the middle of the track o0'
i hope i explain correctly my problem