The ENERCALC Structural Engineering Library user interface is divided into a Main Menu and a Working Area.
The Working Area is used to display the calculation module that you are currently editing. When you choose to view the Project Manager, it is displayed on the left side of the Working Area. See more to follow.
The Main Menu is described in much more detail here: Main Menu description

Working Area - Showing Project Manager
Immediately after a Project File is opened the Project Manager is displayed. As you can see in the image below, the Project Manager occupies a portion of the left side of the screen.
The Project Manager provides you with the ability to control the contents of your Project File. Double-click any calculation to open the associated module and edit the parameters of that calculation. Please click here to jump to detailed information for the Project Manager.

After a calculation is selected for editing, the Project Manager automatically collapses, and the window fills with the user interface for that particular calculation module as shown below:

NOTE: It is normal for the Project Manager to hide while a calculation is being edited.
For a review of using a typical calculation screen click here.