all custom libraries or imported parts
CustomFootprints.pretty has all of the component footprints (used in PCB layout)
AERO_custom_symbols.kicad_sym has all the custom symbols (used in schematic layout)
`3d-models' has all the custom 3d models (used in pcb view)
When managing file paths, be sure to follow the following naming convention:
When importing the symbols library call it AERO_Symbols. When importing the footprint library call it AERO_Footprints. The 3D libary path should be called AERO_3D. If everyone does this, there should not be any "Cannont Find Symbol" Errors. If you encounter this when opening files, your symbol naming could be incorrect.