Code:
0 // CSG commands can be used in subfiles, too
0 // The identifiers are non-global and bound to the file / subfile
0 // It is possible to inline CSG commands from subfiles
0 BFC CERTIFY CCW
0 // SYNTAX 1 0 !LPE [CSG FORM] [ID] [COLOUR] [MATRIX]
0 !LPE CSG_CUBOID a 4 0 0 0 1 0 0 0 1 0 0 0 1
0 !LPE CSG_ELLIPSOID b 1 0 0 0 1.35 0 0 0 1.35 0 0 0 1.35
0 !LPE CSG_CYLINDER c 2 0 -1 0 .7 0 0 0 2 0 0 0 .7
0 !LPE CSG_CYLINDER d 2 -1 0 0 0 2 0 .7 0 0 0 0 .7
0 !LPE CSG_CYLINDER e 2 0 0 -1 .7 0 0 0 0 .7 0 2 0
0 // SYNTAX 2 0 !LPE [CSG FUNCTION] [ID] [ID2] [ID3]
0 !LPE CSG_UNION c d d
0 !LPE CSG_UNION d e d
0 !LPE CSG_INTERSECTION a b f
0 !LPE CSG_DIFFERENCE f d f
0 // SYNTAX 3 0 !LPE CSG_COMPILE [ID]
0 // The COMPILE command displays the CSG volume on the screen
0 // Inlining the following line will generate triangles of the CSG volume
0 !LPE CSG_COMPILE f
0 // E.g.
0 // Inlined: !LPE CSG_COMPILE f
3 4 -10 1.5752766 7.3133416 -10 1.5752766 8.313231 -10 3.3930404 7.6749177
3 4 -10 1.5752766 7.3133416 -10 -2.6084895 6.481139 -10 -2.6084895 7.9504156
3 4 -10 1.5752766 7.3133416 -10 -2.6084895 7.9504156 -10 9.094947E-16 8.866396
...
edit: Adjusted transformation matrix syntax to LDraw standard
edit2: changed !LD_PART_EDITOR meta command to !LPE