dynamic sprites jittery

I am doing scaling by hand, because the autoSD does not support yet what I want…
I do that by first exporting my @4 version, then I set scale to 0.5, cut in half my border and shape padding settings, and export @2, then I set scale to 0.25, and cut in half again the border padding and shape padding…
The smallest version, work fine…
But the @2 is jittery, and the @4 even cut parts of the sprite.

How I fix that? I am exporting wrong?

(also, someone has a clue on how to make it organize the sprites always the same way? It is very annoying the behavior of every time I change the scale to organize them differently…) [import]uid: 142895 topic_id: 26995 reply_id: 326995[/import]

Is there any way i can split a sprite in real time without using images? Does corona has an api for this?
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