Problem with Preferences

I am on FM Pro version 5.6.13.
In Preferences=>Authoring=>External Editors, the three populated choices are PS, QT and QT, all of which I have, but I wish to change.

In all three cases, when I click on the up/down arrows I get a number of choices, including the possibility to choose the path to Applications and/or Macintosh HD or my user account. However, when I select any of these, so far as I can see, absolutely nothing happens. When I click on Applications, I would expect a list of my Applications folder would show up so that I might choose a different editor.

Is this a known bug or do I miss something?

“Stantastic” gives the answer to this question elsewhere in this Forum. In Preferences–Authoring when you click on the up/down arrows, do not click on the Applications folder; rather, click on the Choose… heading and this will bring you to the Finder.