From nookDevs

Part of the NookColor portal

You'll need to use 'repo' to work with the CyanogenMod source code. See http://source.android.com/source/git-repo.html for more information about the 'repo' tool.

Downloading Sources

The latest version of CyanogenMod 7 is the 'gingerbread' branch. Get a copy with the following commands:

repo init -u git://github.com/CyanogenMod/android.git -b gingerbread
repo sync

This might take a very long time to finish.

Building CM7

After the sync is complete, use the following procedure to build CM7 for the NOOKcolor:

. build/envsetup.sh
brunch encore

There are many targets defined by the makefiles in build/core for individual parts of CM7, but 'brunch' will build everything. This may take from 10 minutes up to several hours, depending on the speed of your build system.

Create a CM7 SD card

After 'brunch' finishes, you'll find a few files in $OUT:

recovery.img --> rename to uRecRam
kernel --> rename to uRecImg

These are the latest clockworkmod (CWR) v3.0.0.6 w/support for ext4 filesystems.

Also, there's also a script in $OUT called:

sd_ramdisk_packer.sh

Assuming this works, it should repack your $OUT/root (mmc ramdisk) into a uRamdisk that can be used with a bootable SDcard. The stuff in /system would go in the /system partition of the SD card (p2).

The result: a bootable CM7 on SD. It may not be wise to distribute as CyanogenMod for encore is a fast-moving target-- unless you plan to create a new one every day or something.

There is a slightly-themed u-boot.bin in device/bn/encore/prebuilt/boot/. It is simply a recompiled u-boot from BN's source with cooler graphics.