So, let’s assume you have installed or updated to latest kernel-power after installing NITDroid.
Note. kernel-power is compatible with multiboot starting from version 39.
First, make sure you have version 39 or later installed.

Second, you MUST also have the zImage file from kernel-power.
It comes in an optional package kernel-power-bootimg. If in doubt, do this:

Now you can either manually modify the .item file, or you can let multiboot handle it automatically:

This will do everything for you
I hope these instructions were clear to all power users who are tempted to install nitdroid