yes OscarJ you're right, but sometimes, Bauxite can produce colored landscape
Here a little pigs file including 2 scatter's objets, unpack it and have a look in igs file for code.
Target material is not recorded, so it ask to be adjusted in UI if necessary
3 mats are defined : mat1, mat2 and mat3, they can be assign in target individually.
scatter take mesh in proto, not model2.
a new shoot, here I put some particles done with realflow inside c4d, but they come completely black (simple specular like water mat, I don't understand , probably a mesh orientation normal or something like that)
happy rendering