The debug window is used to examine the contents of variables, lists and the OK status variable.

Click on any area to learn what it does.

This window is most useful when single-stepping through a script. To watch a variable value, you have to add it by double clicking the variable name itself in the script window or by right clicking the debug window to get the popup menu:

Click on any area to learn what it does.

and then selecting "Add item to window" to get the dialog below:

The IDE will support up to 10 breakpoints and bookmarks per source file. There is a limit of 20 breakpoints in total for a program.         

When running a multi-file project, it isn't necessary to open all files used in a program in editor windows. The debugger will automatically open a file in an editor window if an error occurs on a line within the file.