[Barnes & Noble Nook Tablet] JAS6377:
For anyone coming late to the party and unable to find the recovery image to properly repartition your Nook Tablet, I may have some useful information. I was unable to find a version of the recovery that allowed for repartitioning, so I took a few days to look around at what options were available. I settled on just manually repartitioning.

**DISCLAIMER**

I'm a mechanical engineer, not a developer. Perform any of this at your own risk. I'm not responsible for bricked devices. This is only tested on the NT 16GB as that's all I have. UNLESS YOU BACKUP YOUR DATA PARTITION, THIS PROCESS WILL WIPE IT COMPLETELY. It completely obliterates the last 4 partitions and rebuilds them, so be warned.

So, to start off, I wanted about 2GB of /system to match what @chrmhoffman's custom recovery did. Thanks to @grantd, we were given that earlier in the thread here. Using this partitioning scheme, a bootable CWM SD card (so I could use parted instead of sgdisk, because I'm a wimp and like directions), and the instructions here, I kind of halfway cobbled together a solution that seems to work. At least my NT boots. And has GApps. So there's that?

On to the process:

1. Boot NT into CWM recovery on the SD card

2. Through the CWM menu on the device, unmount the /cache partition. You may need to unmount another as well, but on mine, only /cache was mounted initially.

3. Execute the following commands (commands are red and bolded, the rest is output).

4. Once you're satisfied with your partition table, exit ADB and reboot the device into your emmc recovery. I'll assume people are using later versions of TWRP at this point.

5. Inside TWRP, go to "Wipe" > "Advanced Wipe" and check "System". Then tap "Repair or Change Filesystem" > "Change File System" > "EXT4". Do this for Cache and Data as well. The parted commands below only generate ext3 filesystems, and I was too lazy to figure out how to do it myself in parted and/or sgdisk.

6. Flash your ROM and GApps package and have a ball with your newly invigorated Nook Tablet. We also get some bonus device data storage out of this, since userdata and media are merged into a single partition. Yay!

**Note: For some reason, the AOSP 7.1 ROM located in the Notre Dame Box kept resizing the system partition to ~644MB or thereabouts... I have no idea why. I had to go for lnos_acclaim-ota-NJH47F.180713, at which point I had my full storage available in /system, which I used to install GApps Pico :D.

~ >[B][COLOR="Red"]adb shell[/COLOR][/B]

~ # [B][COLOR="Red"]parted /dev/block/mmcblk0[/COLOR][/B]

(parted) [B][COLOR="red"]print[/COLOR][/B]
print
Error: The backup GPT table is not at the end of the disk, as it should be.
This might mean that another operating system believes the disk is smaller.
Fix, by moving the backup to the end (and removing the old backup)?
Fix/Ignore/Cancel? [B][COLOR="red"]f[/COLOR][/B]
f
Warning: Not all of the space available to /dev/block/mmcblk0 appears to be
used, you can fix the GPT to use all of the space (an extra 593888 blocks) or
continue with the current setting?
Fix/Ignore? [B][COLOR="red"]f[/COLOR][/B]
f
Model: MMC 016G4A (sd/mmc)
Disk /dev/block/mmcblk0: 15.9GB
Sector size (logical/physical): 512B/512B
Partition Table: gpt

Number Start End Size File system Name Flags
1 131kB 262kB 131kB xloader
2 262kB 524kB 262kB bootloader
3 524kB 16.3MB 15.7MB recovery
4 16.8MB 33.6MB 16.8MB boot
5 33.6MB 83.9MB 50.3MB fat32 rom
6 83.9MB 134MB 50.3MB fat32 bootdata
7 134MB 522MB 388MB ext4 factory
8 522MB 1164MB 642MB ext2 system
9 1164MB 1611MB 447MB ext4 cache
10 1611MB 9630MB 8020MB fat32 media
11 9630MB 15.6GB 6004MB ext4 userdata

(parted) [B][COLOR="red"]rm 11[/COLOR][/B]
rm 11
(parted) [B][COLOR="red"]rm 10[/COLOR][/B]
rm 10
(parted) [B][COLOR="red"]rm 9[/COLOR][/B]
rm 9
(parted) [B][COLOR="red"]rm 8[/COLOR][/B]
rm 8

(parted) [B][COLOR="red"]mkpartfs primary ext2[/COLOR][/B]
mkpartfs primary ext2
Start? [B][COLOR="red"]522[/COLOR][/B]
522
End? [B][COLOR="red"]2522[/COLOR][/B]
2522

(parted) [B][COLOR="red"]mkpartfs primary ext2[/COLOR][/B]
mkpartfs primary ext2
Start? [B][COLOR="red"]2522[/COLOR][/B]
2522
End? [B][COLOR="red"]3000[/COLOR][/B]
3000

(parted) [B][COLOR="red"]mkpartfs primary ext2[/COLOR][/B]
mkpartfs primary ext2
Start? [B][COLOR="red"]3000[/COLOR][/B]
3000
End? [B][COLOR="red"]15.6GB[/COLOR][/B]
15.6GB

(parted) [B][COLOR="red"]name 8 system[/COLOR][/B]
name 8 system
(parted) [B][COLOR="red"]name 9 cache[/COLOR][/B]
name 9 cache
(parted) [B][COLOR="red"]name 10 userdata[/COLOR][/B]
name 10 userdata

(parted) [B][COLOR="red"]quit[/COLOR][/B]

~ # [B][COLOR="red"]tune2fs -j /dev/block/mmcblk0p8[/COLOR][/B]
tune2fs 1.41.6 (30-May-2009)
Creating journal inode: done
This filesystem will be automatically checked every 30 mounts or
0 days, whichever comes first. Use tune2fs -c or -i to override.
~ # [B][COLOR="red"]tune2fs -j /dev/block/mmcblk0p9[/COLOR][/B]
tune2fs 1.41.6 (30-May-2009)
Creating journal inode: done
This filesystem will be automatically checked every 30 mounts or
0 days, whichever comes first. Use tune2fs -c or -i to override.
~ # [B][COLOR="red"]tune2fs -j /dev/block/mmcblk0p10[/COLOR][/B]
tune2fs 1.41.6 (30-May-2009)
Creating journal inode: done
This filesystem will be automatically checked every 30 mounts or
0 days, whichever comes first. Use tune2fs -c or -i to override.

~ # [B][COLOR="red"]e2fsck -fDp /dev/block/mmcblk0p8[/COLOR][/B]
/dev/block/mmcblk0p8: 11/977032 files (0.0% non-contiguous), 155617/1952939 blocks
~ # [B][COLOR="red"]e2fsck -fDp /dev/block/mmcblk0p9[/COLOR][/B]
/dev/block/mmcblk0p9: 11/233472 files (0.0% non-contiguous), 37564/466797 blocks
~ # [B][COLOR="red"]e2fsck -fDp /dev/block/mmcblk0p10[/COLOR][/B]
/dev/block/mmcblk0p10: 11/1579936 files (0.0% non-contiguous), 82401/3158773 blocks

~ # [B][COLOR="red"]parted /dev/block/mmcblk0[/COLOR][/B]
GNU Parted 1.8.8.1.179-aef3
Using /dev/block/mmcblk0
Welcome to GNU Parted! Type 'help' to view a list of commands.
(parted) [B][COLOR="red"]print[/COLOR][/B]
print
Model: MMC 016G4A (sd/mmc)
Disk /dev/block/mmcblk0: 15.9GB
Sector size (logical/physical): 512B/512B
Partition Table: gpt

Number Start End Size File system Name Flags
1 131kB 262kB 131kB xloader
2 262kB 524kB 262kB bootloader
3 524kB 16.3MB 15.7MB recovery
4 16.8MB 33.6MB 16.8MB boot
5 33.6MB 83.9MB 50.3MB fat32 rom
6 83.9MB 134MB 50.3MB fat32 bootdata
7 134MB 522MB 388MB ext4 factory
8 522MB 2522MB 2000MB ext3 system
9 2522MB 3000MB 478MB ext3 cache
10 3000MB 15.9GB 12.9GB ext3 userdata

So essentially what we're doing here is nuking the last 4 partitions back to and including /system, rebuilding /system with 2GB-ish of space, then allocating the rest to /cache and /data.