Finally, reflashing again fixed those problems.
But now, on v1.71, the cam still doesn't seem to work (same error with VLC) :(
[ 456.055480] usb 2-2: new high-speed USB device number 2 using ehci-omap
[ 456.247436] usb 2-2: New USB device found, idVendor=045e, idProduct=0772
[ 456.247467]...