Tips for solving the pentachoron with edge length 3
You can solve the 5 face pieces (4 differently colored octahedra) without the need of macros or commutators. The 5 four-colored corners can be solved only using slice 3 twists. Finally comes the hard part, solving the 10 three-colored edge pieces.
Most commutators of 2-slice twists only have effects on the edge pieces. With that you can place all edge pieces in their correct location, possibly flipped.
After that Matthew's "flip" and "turn" macros are very helpful in properly orienting the edge pieces.
Here is an illustration of these macros, their references r1 to r3 and their effect.