If you snapshot a TP, the pivot is based on the TP icon position, and MatIDs are incremented by 1 since the TP object itself is assigned a material slot.
Export and ParticleToObj both retain proper MatIDs.
Material IDs are a little tricky in TP because 3dsmax requires each object have only one top-level material (e.g. multimaterial).
In order for TP to import multiple objects with different materials it must dynamically re-allocate material ID assignments based on the number of incoming materials.
Export and ParticleToObj are able to create nodes in the scene with the correct materials since they know the material look-up table.