A: Yes, it can hold a standard power armor suit.
A: You must not have the jet pack mod for your power suit. Also you can't climb ladders in fallout.
A: It should, but be aware that it is pretty heavy. Even with a very light weight fiberglass ladder it is difficult to navigate.
A: If it's a standard wooden extension ladder I see no reason why it wouldn't. I don't think it would work on what I consider a standard wooden ladder meaning the kind that folds out with a work tray on it.
A: Yes, this item could attach to a standard wooden ladder if it's the right size.
A: It depends on the configuration. It will not connect on the top extension. It will connect to the middle portion of the ladder.
A: I would not recommend it - further from the wall means more chance to wobble.
A: I would not recommend it - away from the wall you have more chance to wobble.