<< Get Selected is correct message to use, but the placement for it seems to be a bit wrong. When do you want to print it to log? When selection is changed? When some button is pressed?
Below are few examples, maybe you just placed some brackets to wrong place:
Names Default To Here(1);
nw = New Window("Example",
b = List Box({"single", "double", "triple"}, nlines(10));
);
wait(1);
b << Set Selected(2);
wait(1);
show(b << get selected);
wait(1);
nw << Close Window;
New Window("Example",
b = List Box({"single", "double", "triple"}, nlines(10), show(b << get selected));
);
-Jarmo