I fixed it with sd maid, running the corps cleaner. I'm on lolipop.
I've had my case almost 10 months and its still good. My only complaint is that the PU letter part scratches easily, and the metal part has worn down to a coppery color on the screen side, I guess it's from rubing against the plastic edge. But fun...
I believe that is the Android version the Shield shipped with, not the current version.
That's was the original version, but for example, my Shield shipped with 5.0.1, i didn't have to update.
Not sure how it works with cwm, not sure if there's a fine manager. But in twrp try mounting system, go in to advanced>file manager and go to the folder 'system' and rename the file 'recovery-from-boot.p' to 'recovery-from-boot.bak' or something e...