Still no Sleep of Death here after a few months of using CyanogenMod 7.1 for myself. For others still experiencing this problem it might help to go in and backup all of your data with a backup app like "titanium backup" and go in and wipe BOTH the data and caches in your eMMC using clockworkmod through the supplied app "ROM Manager", then re-flashing a stable of cyanogenMod 7.1. I conclude this might be a problem for some of you that are updating your custom ROM and layering in build kernels if the patch mentioned in this thread is not working. I also had this problem with the Release Candidate build of cyanogenmod 7.1 and had to do a total rewipe of my emmc to get rid of this problem. Others in this thread here have had good luck reflashing a nightly with a patch in this thread here so check that thread out also in box 4. http://forum.cyanoge...ver-from-sleep/
I know this solution is a hassle but it is worth a try if you are still having problems after all of this time after applying the custom kernel patch supplied at the beginning of this thread by the user "Embedded". I myself have not tried his custom kernel patch as I no longer had this problem after a total rewipe of data and caches in my eMMC from the Release Candidate build of cyanogenMod 7.1 a few months back.
This might seem to be a matter of course but make sure you are selecting the power down menu for your nook color by long pressing on the power button. Just hitting the power button quickly on your nook does not power down cyanogenmod, all it does is turn your screen off. CyanogenMod is still using processes of apps wanting wifi and updating, and using your battery in the background of your device. I think this method was implemented by the developers for power users that put down and pick up their nook during the day, as the screen back-light uses up most of your battery.
I have noticed when I forget to power down my nook overnight that it acts like that "Screen of death" but it is just a dead battery where I pick up the nook, I hit the power button and get a blank screen, where cyanogenmod does not have enough battery power to boot up until I plug it in and charge it for awhile. Sometimes I get a icon notice with a nook and a lighting bolt symbol underneath that I conclude means it is a dead battery, sometimes not if that battery is way past dead. So keep that problem in consideration.
Shouldn't the nook color enter some sort of deep sleep mode to conserve the battery of the course of a few days even if you forget to plug in your nook, and also forget to choose the power off option in the menu? I think it should and this could be some sort of bug.