Interestingly trying to work around the inability of my nook to upgrade over the air (see my previous post), discovered that the old way of manual update listed at
this page kind of works on glowlight 4. So if I connect the device to the PC and copy update.zip file into to root of the storage drive then after disconnecting and about 50 seconds, Nook unexpectedly restarts and tries to upgrade the system. The only problem in my case was that the 8.1.4.43(A)->8.1.4.45 (downloaded from the link posted several times here and with https proto just in case) doesn't work with an error "Install failed'. It restores to the previous state, but mission was not complete unfortunately...