if it's anything like my 5DIII remember you can't use Live View when using a flash..
It doesn't trigger the flash when using Live view..
My 560's work fine with both on 5D3 and 5D2 and with triggers...
As said before, there are no firmware's on Yongnuo flashes that can be upgraded..
They're as stupid as a flash gets..
Great flashes/strobes though..