YafaRay Rendering Software

[micheus]

when editing a materials properties; you can see a preview of how it will look like in Wings but there is no preview in the Yafaray tab. Is it because it can't tell you what it will look like after rendering before rendering?

Yes.
The best it could be done is to create a preview for the material being edited similar to that sphere used in Wings3D's material. But, that would need to be implemented - it doesn't exists in the plugin.