I think the problem is due to the alpha channel present in the image.
It is imported inside CinGG by removing the transparency and
converting it to white. See attached image. I lose transparency with
both png and exr, so it is a problem with CinGG (or me getting
something wrong) and not the images. I have been using the RGBA-FLOAT
color model.
Does problem present with both native and ffmpeg decoders?
A long time ago it seems to me that there was talk of problems with
importing sources with alpha channel, but I can't find it again.