Altium CM3 IO pcbdoc file is actually the CM3 Industrial #56
Description
cm3\radxa-cm3-io-board\altium\radxa_cm3_io_board_v1330_pcb_layout.PrjPcb\radxa_cm3_io_board_v1330_pcb_layout.PcbDoc
The above file when opened in Altium contains the PCB layout of the CM3 Industrial IO board not the standard one. I can't find the files for the standard IO board.
Also there is only the schematic library file in the folder: cm3\radxa-cm3-io-board\altium\radxa_cm3_io_board_v1330_schematic.PrjPcb
There are no footprint libraries to be found.