How to reproduce the "error":
- Type in an existing city (say Hamburg) and click the button
- Click on "Get Directions from another place" (will appear just above the map)
- Type in a not existing city (say xxxxx) and click the button
- The visual and textual directions disappear
- Click on "Get Directions from another place"
- Take an existing city again and click the button
- Polyline does not show, no blowup appears when clicking on any step
- Redo 4. and 5.
- This time everything works fine