staff of saruman fallen istar's stave can be played on gandalf, and doesn't get discarded at the end of the turn. Are these correct?
Here is what rules have to say about playing shadow possessions (and artifacts):
A Shadow player cannot play a Shadow artifact, condition, or possession on another Shadow player's minion, or to another player's support area. However, Shadow cards may give bonuses or other game effects to other players' Shadow cards, and Shadow players may play events for other players' Shadow cards as appropriate.
As you can see, the rules only prohibit playing the staff on another Shadow player's minion, but it's ok to play it on FP player's character. The staff also specifies it has to be played on a Wizard, and Gandalf (and
Radagast) is a Wizard. Since in Shadow, only Saruman is a Wizard, I'm led to believe it was intentional to allow playing this staff on Gandalf or
Radagast.