User Activity

I attached the Compact Battery Pack CP-E4 to my Speedlite 600EX-RT and it will not power on. The battries are fully charged. The flash works with the battries installed in the flash unit. Is there some thing else that I am suppose to do?
I have the canon 5d mark III, when used in manual as I half press the shutter button the marker when zeroed out or located where I want it to be for the exposure will show a second marker. Why does it do that?