List connector does not return or handle errors

The list connector is not returning errors on saves, giving the appearance that failed exports are successful. Handling should be added to the ModifyListItemAndReturnId method such that the connector can handle messages such as the following (where an update is attempted on a non-existent list item):

<Results xmlns="http://schemas.microsoft.com/sharepoint/soap/"><Result ID="1,Upd
ate"><ErrorCode>0x81020016</ErrorCode><ErrorText>Item does not exist

The page you selected contains an item that does not exist.  It may have been de
leted by another user.</ErrorText></Result></Results>

Estimate includes testing