Hi, I'm assuming that either you are trying to use multiple source code files to create your program, whick is perfectly ok or wishing to add external media e.g images, 3D objects etc.
To use multiple source code files open up your Solution Explorer, right-click on the projects folder and add or import the file you wish to include in your project, note that these have to be .dba source files and located in the projects folder (if it isn't already just copy/paste into the projects folder). You should now be able to use functions and subroutines from the included folder.
If you are trying to add media, images etc, then open up the media tab and click the folder icon to add media, again it is easier if the media is already located in your projects folder. This eliminates the need for a long path when loading the desired media.
Hope this helps
A clever person solves a problem, a wise person avoids it - Albert Einstein