Bump, strange light/shadow effects

[synolog]

A6.3 - Using the attached texture i've found that the bump seems inverted in the upper face of the cube. The c4d AR is more accurate.

Strange displacement result.

[houska]

I think it has something to do with normals, see the bug report here, it's probably the same issue:

https://forum.corona-renderer.com/index.php/topic,15469.0.html