Most of non-Apple-keyboards works well in OF - there just a few exotic or lowcost CE types, which won't work ( CE = China developed Equippement ). In some cases keyboards are not recognized during OF-startup, but that behavior above I've never seen.....
Probably the keyboard-matrix generates a wrong code during initialisation, which MAC interprets as "Tray-open".
Would be interresting, what happens when Caps-Lock is pressed during startup