The code below has to be copied into the built-out TerrainStyle.artdef file after Modbuddy build within the FEATURE_WULINGYUAN element, TerrainAsset param:
<Element class="AssetObjects..BLPEntryValue">
<m_EntryName text="ART_DEF_TERRAIN_ASSET_NWON_HALONGBAY"/>
<m_XLPClass text="TerrainAsset"/>
<m_XLPPath text="TerrainAssetSet_Base.xlp"/>
<m_BLPPackage text="terrain/TerrainAssetSet_Base"/>
<m_LibraryName text="TerrainAsset"/>
<m_ParamName text="TerrainAsset"/>
</Element>
This is because the Ha Long Bay asset is not available in the SDK Assets and so the entry is blanked out by the build.