My english isn't good too :-)
With command 4 you get inspector tab at right.
So you get effects tab. Go to transform....scale...click little arrow at left to get X and Y values.
Y value at 50%
Also, remember that you can now set a manual aspect ratio for the project - this means that you are no longer stuck with 1920x1080 & the black bars, but can now choose to stretch & not only squeeze the footage.
This means you can get 3840x1080 & not just 1920x540 - it should mean that you could also choose other aspect ratios such as 2.93:1 or 2.66:1 & automatically crop the footage by adjusting the x or y axis in the Transform tab.
