Thank you for very fast reply, I got it working by changing the mapping of the sphere in which the user is located. However it feels like the user is tiny and close objects seem to be big.
Is there a way to compensate that ?
I had tried to convert it to DDS somehow, I dont have photoshop, so I had used the ModifiedCubeMapGen, but the output is always just the colored spaces and not the texture, do you have any experience with that tool ?