I have fully embraced the graphical designer e.g. because there are quite a few things you can do more simple and faster in the graphical designer compared to the green screen. I will here list a few tips if you should not know them already:

Changing the font for many elements
If you want to change the font used for many remap window and/or tabulator elements into the same font, then you only need to mark all the elements at a time either by holding <Ctrl> and cliking on each element or by grouping them together by draging around them all in the result view. You can also mark all elements by pressing the <Ctrl> key and 'A' simultaniously.
Now the lower left window will show the common font (if there is one) and you can now change the font for all elements simply by selecting it here.

Marking the interval of positions for an if..then (or conditioned) line
When you insert a conditioned overlay you simply mark the interval of lines with the left mouse key, but did you know that you could use the right mouse key to mark out the interval of positions? It makes it somewhat faster to specify those positions. When remapping in the conditioned overlay you of course do that via the conditional tab in the input window.

Copying lines from another overlay
If you want to copy lines from another overlay you just open the other overlay (as a conditioned overlay or suboverlay). Now mark the lines you would like to copy and simply use the clipboard to copy and paste into the main overlay. This works if you select the elements in the element list on the upper left. You can of course also copy lines within the same overlay in the same manner.

Making the graphical designer start faster (cache fonts)
Some customers are working remotely (perhaps on a different continent) when accessing the System i. That can make the communication between the designer and the host quite slow. If a user is experiencing this you can suggest to cache the fonts locally on the PC instead of downloading them each time when starting the PC. The new/changed fonts can be loaded when necessary by selecting this in the designer: 'File' and 'Reload fonts and colors'. You enable caching of fonts and colors by selecting the 'Advanced settings' tab in the signon window and select 'Use local cache of colors and fonts if available'.

You have read the book now watch the movie ;-)
You have of course read the manual, but why not watch the movie?
There is a movie showing advanced use of the conditioned overlays right here: http://download.interform400.com/shares/public/How_to_call_a_conditioned_overlay_with_the_graphical_designer.wmv

As not many actually read the manuals I am seriously considering to do many other movies showing how to do specific things in InterForm400 and the related modules. The movies will not be fancy, but very informative and technical. Feel free to contact me if you have any requests!