Just so you guys know, I had submitted a bug report earlier, but it was under "Profile" and I just wanted to make it clear on the forum.
Found a bug where adding Runes to your rune page requires that you move your mouse off of the rune before it allows you to double-click add. The step to create the bug are as follows:
1. Create a new Rune Page
2. Add in a Rune (Any Rune) by double-clicking a rune. Don't move the mouse.
3. Rune added to rune page.
4. Double click same rune without moving mouse.
5. Rune was not added.
Once you move the mouse, the rune can be added into the rune page by double-clicking on the run again, and the steps are as follows:
1. Create new Rune Page
2. Add in a Rune (Any Rune) by double-click a rune.
3. Move the mouse off of the added rune.
4. Move mouse back onto the same run, add.
Not sure if anyone else ran into this issue, and seems to be a very small bug, but was still a bit of a UX nuisance.