Ye, the game warned me about the potential for glitches ("you have driver version 2.x.y, we recommend at least 21.a.b") so I have nothing to complain about. It may be that it needs the amdgpu-pro driver.
Perhaps the portcullis could be somehow visually connected to the disc, I though the disc was supposed to help you do a cool movement trick but could not figure it out. Oh by the way I really enjoyed the air controls / movement style!