You can use conditional aborts for both of those cases. If you haven't seen the BD/UCC video I recommend taking a look at that as it has a good explanation of a decently sized behavior tree. In that video I explain conditional aborts as well as what happens when the tree ends.
Hey Justin,i have tried conditional aborts but i can't get it to work correctly, the event just stays in the wander state and never fires after being called again,