AIFP has received a facelift!
Gone are the separate opening screens for the flight plan/repaint installer and the flight plan editor. The flight plan editing controls have been moved to a separate dialog. A new, single Main Panel serves both the installer and editing functions. Most of the controls on the old installer panel remain on the new Main Panel. Functions related to those buttons that have been removed are now accessed via the main menu bar.
All dialogs than can benefit from it, including the Main Panel, are now resizable. Location and size of most dialogs is now saved, both intra- and inter-session. So they will re-open as they were when last closed. You should also find more consistency in operation across all dialogs. For example, a double-click on any Flight Plan, Airport or Aircraft List item opens a suitable editor. Hovering the mouse over any such list item displays a tool tip including more information on the item. A right-click on any such item selects that item and presents a context menu of common operations for that item. The full compliment of operations is, of course, always available from the main menu bar. There is no longer a Download/Install/Substitute Individual Repaints on the Main Panel. To open the Missing ACs dialog, double-click on a missing aircraft in the Aircraft List or right-click for substitute.
Overall, functionality is nearly identical. Nothing has been removed. There are a few minor enhancements, particularly in the handling of bulk traffic files. As well, a few Version 2 issues that were noticed during development have been resolved.
The Version 3 user manual has been extensively reorganized and revised, combining the two earlier manuals and also adding illustrations of most dialogs and lots of "how to" text. Adjusting to the changes should be largely intuitive. If you do have difficulty, please first refer to the user manual before asking for help.
Enjoy,
Don
EDIT: My website was moved to a new server, recently and, it seems, the automatic update service no longer works. So, for the moment, you will not be automatically updated to version 3. However, you may obtain Version 3 directly from the Latest General Release menu item on the AI Flight Planner page at http://stuff4fs.com.