It looks like there might be a bug in the number picker. If requestUpdate gets called while a NumberPicker window is open, I get an Unexpected Type error with no other information. Just "Unexpected Type Error", nothing else.
The attached project causes the error. If line 38 in blahApp is commented out, the error does not happen or if I set the timer period long enough so that I can enter a value into the number picker window before requestUpdate gets called, the error does not happen.