Sorry, there's no way to reorder them in the UI at the moment. You've basically got two options:
A. Hand edit them to be in the order you want. Change the connection details of the first one in the list so that it's the users/host/port you'd like first in the list. Ditto for the second through 15th connection.
B. Re-order them from the JavaScript console.
Option B goes like this...
1. Press Ctrl-Shift-J to open the JS console.
2. Type: nassh_.prefs_.get('profile-ids')
This will return the list of profile ids, in the order they appear in the UI. I've got three profiles, and the ids are: ["aad3", "51fc", "ee3f"]. Your list will be different. Save it somewhere in case things go wrong.
3. Type: nassh_.prefs_.set('profile-ids', [ ... ]), except replace [ ... ] with the array of profile-ids reordered to your taste.
Rob.