You can insert the value of a variable into any text field as follows:
In the run-time Autoplay Menu Designer automatically substitutes the actual value of that variable in to the resulting text. A good example to this is texture path shown in the Properties Panel when you add a texture to some object, in particular, it is displayed as:
where <filename> is the file name of the texture, and RESOURCES is a variable that holds the path to resources of the project. In the run-time it will be expanded to the actual path.