Using this button the saved project (.bld ) file can be loaded in to the Smart InstallBuilder(8.2).While loading the project file the respective files in the folders represented by the project file must be in tact and all files must be available failing which the project file will fail to open.The .bld has file association with the exe file and it will be identified with the icon of exe file and it can be opened right from the folder by right click and select 'open bld file' menu.
[F3] is used as shortcut to 'Open' button.
The select window will appear as below.

The window will appear with files if any with .bld extension and it can be selected to open the project.
The builder interface showing the open project is as shown below.

Add Files [ALT+F2]