This can be a fiddly process:
In the Environment, create a new Mapped Instrument Object, and cable it up to the Instrument Channel you are using.
Assign the Arrange track to that Mapped Instrument (variety of methods, try dragging from the Environment directly to the Arrange track header)
In the Score Editor, create a duplicate #drums style
You are now ready to go back to the Environment Mapped Instrument, start changing note-heads, transpositions of individual notes, and their group assignments.
If needed, go back to the new drums style, and add/change groups/voice assignments etc.