Moho Forum

I want to know if there's a script or a technique to force AS to find the lost path of images layers whitout importing them one at a time twice ? (like softwares such as After effects or Première do)

There's a script called Relink LostImages by the forum user macton here; viewtopic.php?t=2448. It should do what you want.
Otherwise you can always do a search and replace on the anme-file itself for the path.

The script works but my images layers are resized (at their original size?). Is there a method to avoid that?

Then try method two. I use it quite a lot and the easiest way is to use some advanced text editor, like Scite which is for programming but work very well for these sort of tasks as well.
Open up the anme-file in Scite, select the path you want to change (search on the name of one of the images to quickly find one), then you choose Replace from the Search-meny and fill in the new path. Hit replace all and save thet file with a new name.