Hi,
Both the problem of the LEDs not updating when they should (the listbox & slider not having the expected result), and the possible hang when stopping the dashboard, seem to be related to getting too many shared variable updates from the server.
A workaround should be to put a Wait (ms) primitive in the inner loop, and to wait (for example) 100ms between iterations. Making this change, and the others Adam mentioned, everything seems to work as expected (changing the listbox selection will affect which LED changes when the slider is moved around).
