Are you wanting to customize what Gameguru has or create your own in game one.
The first can be done in your paint program and change the existing graphics in the following folders.
C:\Program Files (x86)\Steam\steamapps\common\Game Guru\Fileslanguagebank
There are two folders of graphics in there.
C:\Program Files (x86)\Steam\steamapps\common\Game Guru\Files\titlesbank
had example of others, and the default one you normally see.
Change these graphics and then build your stand alone build.
For the second:
If you need more then what you will find in the languagebank folder inside your game, then you will have to script up some textbox stuff.
May I also direct your attention to the past twitch tv broadcasts.
http://www.twitch.tv/gamegurulee/profile
There is a wealth if information in these videos from the programmers themselves.
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