Read the documentation and the UV values are not what the documentation states.  The SPS uses only one material, so only one texture.However you can choose, per particle, which part of the texture you want to apply to this particle with the uvs particle property.This property is a Vector4 and is initially set to (0, 0, 1, 1) for each particle (or to initial UVs values if the model had UVs per face),  I have a single mesh, a single material and an array of 48 UV values. First) The