Let me try to explain what happened:
I have sprite with 7 frames, each one has a different character.
I created a new sprite using one of the characters image. When I run the game inside C2 it works fine, but when I export it, the character I used on the second sprite is removed from the first sprite's atlas and that messed up with my game. I had to created a different image to use on the second sprite to make it work corretly.
The bug: two sprites sharing the same .png file isn't working.
C2 version: 152