First off, I think V2 is really wonderful. I really appreciate the addition of phrase search and the directory modifiers. Those are two great features (IMO).
I was playing around and discovered the following: When using the arrow keys to navigate folder structures in the results pane, the focus switches back the search box after pressing one arrow key. For navigation purposes, I think it would be better for the results pane to maintain focus, so that the user can keep stepping through the directory hierarchy, rather than having to hit the down arrow to get focus back to the results pane. This fits in the realm of being a minor annoyance, but I think maintaining focus (if not hard to do) is the way to go.
Also, I note that when the path you are navigating contains a "-", that the part of the path after the "-" gets parsed out and appended to the end of the path string in the search box. IMO, this is a minor thing, and I'm not sure how you'd fix this without changing the "-" modifier to a character that is not acceptible in folder or file names.