I tested the tank in B6.1 and it loaded a little slow but came in just fine...  I walk around the tank to smooth out the cylinders objects,,,  and gave it this quick hdr..  The image is a little dark and towards the blue green spectrum...  small size...640 x 480..  and normal anti aliasing,,   I also did a few regular renders without hdr... I will try Studio... later.... 

It work fine...

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