kimpipes ... sorry, but that is not what the Billboard control is used for. It is used, for example, on the ProgressDlg to display the dynamic text that tells you what is going on at any given time.
all ... What you are attemping to do can be done with a bit of ingenuity. What you will want to do is to create a 'larger than usual' dialog that should contain a bitmap image and whatever text you want to put on it. Make the dialog modeless, and display it early in the game. You will want to play with the formatting a bit until you get something you like.
Then modify your other dialogs (which are generally modal) to add the value 16 to the dialog attributes. This keeps modeless dialogs. Finally, make sure that the final dialog in your sequence does not keep the modeless dialog so that it eventually gets deleted.
I use a slightly different method with my installs. I have replaced the standard bitmap on the generic dialogs with a custom bitmap for our product. I have also changed the bannerbmp to be customized to our install. Then I don't use the modeless dialog in the background.