I'm looking for a solution for this. I need help aligning/snapping a shape to a corner in Illustrator CC. What I really want to do is place a path on top of another, EXACTLY on top. Here's a picture of the scenario:
I've finally found a way to do this with a plug-in called "SubScribe". It's an awesome plugin that you can download for free, by Astute Graphics. Here's the link: http://astutegraphics.com/software/subscribe/
Here's a quick tutorial:
1) Click and hold "Circle by 2 or 3 points" and select "Tanget Circle":
2) Click on a path and then click on the other path across it:
3) Choose the radius of the circle you want to create. It'll automatically snap to the corner.
4) Voi là! You have a circle perfectly snapped to a corner. DONE.
I got it to work by using smart paths and then adjusting with keyboard in outline mode zoomed in. Not an easy exact way but doable.