you can't pick up the ring with the ring hero of your faction, the witch king in angmar faction is the ring hero so that's why you coulnd't piked up, but ones you have it with other unit or other hero you have to give it to the ring hero like the witch king in this case, and so he will have new skin and new powers, the ring heroes are:
Angmar: witch king
Modor : Gorthaur ( he will become sauron after you give him the ring)
Isengat: Saruman
Goblings: Kandra (Shelob) or you can place the ring into the dragon armory of the goblings and Smaug will be avalible for you (recomended)
Gondor: Denethor or Gandalf
Lothlorien: Galadriel ( here you will choise between good or bad Galadriel, see your self what hapens, but if y you decide for a Dark galadriel, the optios to recluit mirkwood units and ents will be no more)
Imladris: Erlond or Glofindel (when he have the ring he will have the power of resurrect Arwen Erlond and and Gwaihir, it has to be in the same place the person die)
Dwarfs: like the goblings smaug you have place the ring into the Mausoleum of Durin, and Durin will become avalible
Rohan: Radagast (he can use the ring to summon a tornado for a set time)
i hope this helps you, sorry for my english
For the spells, you will have to be more specific, and i gladly will help you, enjoy...
Question: When will be released the 3.3 version?