DA_REMOVE_PREF_MAT deletes a material from the Preferred Materials List.
-->(DA_REMOVE_PREF_MAT)---+-----(:DA_MATERIAL)----|string|---+--> | | +-------<-----------<--------------+
:DA_MATERIAL
- enables selection of the material to be removed from the Preferred Materials List.
All input strings must be enclosed by double quotes (" ").