Wall Worm now supports the PBR Material  (Metal/Rough) for exports. This material will now export for both Source and Source 2. This material, which is available in most newer versions of 3ds Max, is a very close match to the material in Source 2.

When exporting to Source 2, the material will export as a VMAT file.

Learn more about the PBR Material in Max.

Wall Worm adds a custom attribute to this material when exporting that also adds a few extra Source 2 parameters (as well as the legacy Source custom attribute*). Those parameters allow controlling extra settings such as 2-Sided.

*Note: In a future update, the legacy custom attribute will no longer be added when the game settings are set to Source 2.