The example design is not generated by default. The example design is generated by user request and can be opened in a new instance of Vivado. This allows you to view and modify the example of various cores being used without touching their own design.
To generate the example design, right-click on a TMR Manager IP instance in a Block Design or on the XCI file under Design Sources and select Open IP Example Design .
TIP: Take a look at the Tcl file instancename _exdes_bd.tcl under Design Sources in the example to examine the script used to generate the entire Block Design.