Two issues, shown in this video (note, both are used in remote-xml mode):
When typing in the combo, the first entry is selected (blue), so if the user hits enter, it does not select the selected one. So either we need to not have one selected by default, or have enter select the selected one (ideal).
In certain circumstances, when an item is selected, then cleared out, the label gets cleared, but not the value. so on the server side, it thinks the user selected an item, but instead, blank should be sent.