#1 What TX are you using? is it a computer TX, does it have a throttle curve set.?

#2 No, that is how it works and you have to live with it. The ESC was never designed for a heli tail. It thinks that full left rudder is "zero throttle on a plane". It needs to see zero throttle to initialise - a safety feature. If it were on a plane you would not want it initialising on anything other than 0 throttle, else you would chop your fingers off!

I use the same tail esc. It's fine.