from looking at the camera manual and the bbv tx1000 manual. I would think you need the switches set for EXTERNAL PROTOCOL CONVERTORS which will be BLUE=0, YELLOW= 1.
if you just apply 24v AC (NOT DC) to pin 5 (blue) and pin 6 (red) and connect the video signal onto your monitor without going through the tx1000 unit you should get a picture- this will let you know that the cameras are providing a picture.
then you need to connect the keyboard data wires gnd/tx and rx to the tx1000 main unit- this sends the control signals to the main unit, then the main unit should convert the data and send it up the co-ax to each camera.
connect the co-ax inputs from the cameras onto the main tx1000 box and check if you have control.
SUMMARY:-
so data from kybd to main unit is rs232 (needs to be wired correctly), then data from main unit to cameras is up the co-ax, power to camera is 24v AC.