Hi all, very similar situation - my Nook HD+ is completely bricked too.
Been a happy user of CM11 on Nook HD+ for about 4 months. I used the guide here to install it.
Then one morning it would not boot - only showing "Nook" screen when powered up. I tried to reinstall CM11 but with no luck.
- I created a bootable SD card with emmc-cwm-early3.img using dd command (dd if=img file of=/dev/sdc bs=1MB). When inserted, Nook would power up and go to Cyanoboot screen and but it would hang there
- I went through 3 different SD cards (all type 4) and they are all same
- I One interesting thing - I found sdcard-cwm-early9.img from http://forum.xda-developers.com/show....php?t=2600572. When I create SD card from it, it actually boots up to CWM screen, and it lets me go through various backup/restore options. However, the image only creates about 120MB of free space in SD card and I cannot place any zip files in it.
The reason for bringing out the last point is that it does seem that my Nook HD+ would boot up from SD card, but not with emmc-cmw-early3.img.
Any pointers would be greatly appreciated. Thanks so much.