Thanks for your questions. Note that our Support Center concept doesn't allow you to post multiple problems within one thread. In the future, please post a separate issue for each question. This way, we can process and track it more efficiently. For now, I've created separate issues on your behalf. We'll get back to you ASAP. See:
Is it possible to change legend's location for 2D pie chart?;
How to apply "Percent" format to Legend;
PieSeries2D - Support resolve overlapping for series labels (if LabelPosition is TwoColumns or Outside).