Parameters are accessed with C4DAtom::GetParameter()/ C4DAtom::SetParameter(). See Parameter IDs.
Parameter: Generate
MGMATRIXOBJECT_MODE
Parameter: TP Group
MGMATRIXOBJECT_PARTICLE_GROUP
Parameter: Follow
MGMATRIXOBJECT_PARTICLE_BLENDFOLLOW
Parameter: Constrain
MGMATRIXOBJECT_PARTICLE_BLENDDIRECT
Parameter: Particle Priority
MGMATRIXOBJECT_TPPRIORITY