Using this Evertz 500FR video distribution frame is quite easy. First, make sure you connect it to the correct power supply. Once it's powered on, you can start using the included amplifier cards for video, clock, and audio distribution. When handling the frame, be gentle to avoid any potential damage to the cards. As for the missing BNC connectors, although it still works, try to be extra careful when plugging in other devices to these areas. For maintenance, keep the frame in a clean and dry environment. Regularly check the cards for any signs of overheating or loose connections. If you notice any issues, it's best to consult a professional technician.