=== advanced: layer usage ===

- E1: fab layers
- E2: mechanical keepout layers
- E3: doc layers: assy and custom
- E4: creating custom doc layers
(- E5: layer compositing: already in C2)
- E6: subcircuit and buffer layer bindings

=== advanced: extended objects ===
- F2: dimension
- F3: cord
- F4: bus
- F5: teardrop

=== advanced (unsorted) ===
- footprint creation basics [5]

