To enable multiple drawings in CET, follow these steps:

1. Go to the File menu and click Control Panel:
2. On the General tab, select the checkbox Enable multiple drawings:

There are two ways multiple drawings can be shown: Either using a single window for all drawings or giving each drawing its own window. This setting can be changed in the Drawings drop-down menu that will appear after multiple drawings has been enabled.

When using a single window for all drawings, you can select your active drawing from the Drawings drop-down menu. When separate windows are used, you will need to open the window that corresponds to the drawing you wish to edit.