Rhino 6 dimension number missing

Hi, I just recently upgrade from v5 to v6 and bump to problems. First, my views always turn black when I click to see whatever views, and turn to normal when I right click and move around. Second, when I use the dimension command, it does not show the number. The picture I provide is a simple 100ft line.

I’m running on mac with parallel by the way, and it used to work fine in v5

Parallels isn’t a supported environment for Rhino 6. The OpenGL support isn’t good enough to cope with Rhino 6 - it demands considerably more of OpenGL than Rhino 5 ever did.

I might downgrade to v5 then. Thanks!