As usually warned during the nandroid backup process, you can ONLY successfully restore a nandroid backup to an IDENTICAL system, straight down to exact ROM version. Anything else ranges from ill-advised to guaranteed failure. The normally-recommended process for hopping through ROMs is to use something like Titanium Backup to backup each of your apps that you care about individually, then restore them when you're on the new system.

As usually warned during the nandroid backup process, you can only be sure of a successful restore of a nandroid backup to an IDENTICAL system, straight down to exact ROM version, as that's exactly what you're restoring: the entire ROM. Anything else ranges from ill-advised, because it will wipe out whatever ROM you're on, to guaranteed failure if the partition sizes differ (which, if I'm not mistaken, they do between 4.4 and 5.0). The normally-recommended process for hopping through ROMs is to use something like Titanium Backup to backup each of your apps that you care about individually, then restore them when you're on the new system. Still, FireLord's answer provides a more complete path using alternate methods.