Movie questions

Spoiler Alert: don't read stuff here unless you don't mind learning things about the movies before watching them.

Interstellar

• Why did the drone screw up?
• Why did the combines screw up?
• How did the whole [circular?!] chain of events get bootstrapped?
  • I.e., the mission would've had to succeed [..in the way it did] for it to have even started [the way it did].
• Also, are we supposed to believe that people however many centuries(?) in the future "saved" him and allowed him to view his daughter's room / affect it? They happened to remember? Did he tell them they'd need to? Or did they just eventually figure out they needed to with their 5-dimensionalness?
  • (And they just happened to let him out near Saturn in time to see what progress had happened and to see his daughter again?)
  • If they could do that, why didn't they do more? I mean, sure, they didn't want to mess with the timeline, but they did, right? Or, rather, they did exactly what the timeline shows they already had done. And back to the bootstrapping question.
    • E.g., how did they know where to send them (open the black hole) if they hadn't already ended up there by them having been told where to go?
• How does a black hole stay put relative to Saturn?