This article provides information on how to fix a PNG image asset that doesn't appear transparent.
Importing a PNG image as an asset in V-Ray for SketchUp that is expected to be transparent can sometimes, instead, appear to be a solid color.
To resolve this, import the PNG file into the project by dragging and dropping it into the viewport.
- Select and right-click on it, then choose Explode
- New material appears in the V-Ray Asset Editor with the same name as the image
- Navigate to the Opacity rollout of the new material
- Enable the Custom Source checkbox for the Diffuse Texture Alpha option.