Hi Subtect !
PBR Materials are currently converted to Custom materials under the hood, and roughness is not part of the supported properties.
Supported properties are :
- Color
- Gloss finish
- Reflectivity
- Transparency
- Blending the base color/transparency with a texture
- Bump map
The focus of this release is to translate the most obvious informations to Unreal.
We do not have a timeline yet for support of more properties out of the box.
Cheers !
Antoine