Hi,
In b21 & b22 I am seeing an issue with the billboard particle effects (set to view mode). The issue is that the right eye is not rendering them correctly, but the left eye is. Here is a screenshot showing the issue.
I am seeing a similar thing with particles in b21, yet it renders OK if I disable shadows for diffused lighting. Can you please check if that is the same for you.
Initially I just turned off shadows on the directional light.
Once I figured out that shadows were the issue I switched to the Valve Renderer and disabled shadows globally, as the Valve render can then manage the shadows, so that is my current work around.