NetHunter2 install on Nexus 10 problems

[J1m]

What I have:
Nexus 10 running 5.1.1
I followed the online instructions.
I installed the Google adb tool
nexus-adb devices - command indicates I'm connected.
I push the Nethunter zip image to /sdcard/
I do Nexus-adb reboot recovery

I am dropped to black screen with icon and "no command"
I'm not given option to install

Questions:
1. prior to all of this do I have to unlock the boot loader?
2. do I have to root the device?
In any event the install is not working per the online instructions.
Any ideas or suggestions anyone?

[jermzz]

Yes you need to root and unlock your bootloader