Sprite sheets cannot be reimported in 4.8 in a project that was converted from an older version

User bug report:
Why do you guys remove the Json Importer from UE 4.8? All atlases from TexturePacker can not be imported anymore on our projects.

Is there a way to activate it? or maybe is there a new way to create texture atlases? Temporally i copied/pasted the PaperJsonImporter to Paper2D source in 4.8 and apparently is working again but i would want to know if maybe there's a new way to make sprites.

UPDATE: Yesterday i could re import an atlas from TextureAtlas just copying the PaperJsonImporter to the source folder but now it's not working anymore.

LoadErrors:Error: Error /Game/Assets/Sprites/Particles/mythoclast_particles : Can't find file for asset. /Script/PaperJsonImporter
UPDATE 2: I deleted the PaperJsonImporter folder again and restore all my old assets (from 4.7 importer), opened the project again (in 4.8) and oh surprise: the new sprite sheet was re imported. I don't get it, pretty confused right now.

UPDATE 3: Re importing only works 1 time. I right clicked my sprite sheet trying to re import it again but got the same /Script/PaperJsonImporter error.

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