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All of this resulted in two warnings and two errors (the errors were predicted by the tutorial). Note that at no time did I do an explicit compile - these errors were automatically discovered reported by the IDE, which I assume did a compile when I saved the window.
The solution to the errors is easy, as explained in the tutorial. They are caused by my renaming the control. Simply right-click on either of the errors and choose Rename all the references. Easy peasy.
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