With Flatten paths unchecked, the names of the regions in the atlas are:
effect_A/power
effect_B/power
With Flatten paths checked, the region names discard the path, using only the image name without the extension:
power
power
This is not allowed
each region name must be unique. I assume you have Flatten paths checked, otherwise please post your settings. You can click Save on the texture packer settings dialog and save a .pack.json file with the settings.
