The Raiser's Edge Gift batch entry requires a valid constituent ID which is why this field is treated as a lookup field for a constituent record and displays as "Constituent Name" in any resulting batch.  Allowing manual entry of constituent IDs could introduce data consistency issues.

The code sample in question which contains the reference to the GIFT_fld_Constit_ID field is found after VBA/API as been unlocked by clicking "Help" > "RE:API/VBA Help" in The Raiser's Edge.  Custom Solutions > API > The API In Action > Gift Batch:
Private Sub CreateBatch() 
    Dim oBatchAPI As CBatchAPI 
    Dim oBatchFields As CBatchFields 
    Set oBatchAPI = New CBatchAPI 
    With oBatchAPI 
        .Init REAPI.SessionContext 
        'Add batch fields 
        Set oBatchFields = .BatchFields 
        With oBatchFields 
            SetupBatchField .Add(), GIFT_fld_Constit_ID 
            SetupBatchField .Add(), GIFT_fld_Amount 
            SetupBatchField .Add(), GIFT_fld_Fund 
            SetupBatchField .Add(), GIFT_fld_Date 
            SetupBatchField .Add(), GIFT_fld_Post_Date 
            SetupBatchField .Add(), GIFT_fld_Post_Status 
        End With 
        Set oBatchFields = Nothing 
    End With 
    Set oBatchAPI = Nothing 
End Function 
Private Sub SetupBatchField(ByVal oBatchField As CBatchField, ByVal lGiftField As 
    With oBatchField 
        .Fields(BatchField_fld_MetaObjectId) = bbmoGIFT 
        .Fields(BatchField_fld_FieldNumber) = lGiftField 
    End With 
End Sub

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