To apply a roughness texture to an object the object is required to have a UV texture mapping. In Shapespark a UV texture mapping comes from the 3D modelling application. If you use SketchUp model as a scene source, the UV texture mapping is imported only if the object has a diffuse texture.
The error states you try to apply a roughness texture to an object without UV texture mapping.
To fix the error you have to modify your source model by adding a diffuse texture to the object. This texture can be even a solid color texture, however its real world dimensions should be the same as the real world dimensions of the roughness texture.