Is there a way to add strings to the string list that are not actually found anywhere else in the system (DM1, text gauge, etc.)? I see that the indirect text widget uses the strings from the list in numerical order and would like to use this to recall text, but the text I want to recall does not exist anywhere else.

In 2.2 there is not an easy way to do this. The only solution in 2.2 is to use the SetWidgetText script method. However, 2.3 will introduce a new programming item for storing and interacting a string. These strings can be managed in scripts (via new scripting methods) as well as allow you to bind strings directly to Text Widgets and Keyboard Widgets. This new functionality effectively replaces both SetWidgetText and Indirect Text although both are still available for backward compatability