Which version of AR are you using?
Is it just this one PSD file exported from ArtRage that is not opening for you in Photoshop?
If you open a different AR painting and export it to PSD, dose it too then fail to open in Photoshop?
Have you tried opening the problem PSD file in any other graphics app? Affinity Photo, Pixelmator, etc… for example to see if it fails there too?