The main window is divided into two sections: Local System and Backup Project.
The folders on your computer are displayed. Use the local folder tree to add items to your project. To see the content of a folder select it in the list and you will be shown its content in the window to the right.
Here your AceBackup project as well as the files and folders which you want to backup are displayed. If you select a folder in the project folder tree its content will be shown in the window to the right. You will find the most important functions in the project toolbar above the project view.