Map an image to have coordinates to get access of the image

The only thing I did with Gimp was open the EXR file, and exported as HDR file changing the file extension.

I’ve created a test project, with the HDR image, and I have uploaded it to Github if you want to check it. I’ll do it because I’m not sure if my texture is correct and I don’t know how can I know it. It blows my mind what you’ve said: