This Goes In The "LostFocus" Method of a ComboBox:

If !Empty(selFactura)
        xFactura = FacturaS.Factura
	xValor   = FacturaS.Valor
	xBalance = FacturaS.Balance

        Select FacturaSC
	   Append Blank
	      Replace FacturaSC.Factura With xFactura
	      Replace FacturaSC.Valor   With xValor
	      Replace FacturaSC.Balance With xBalance
				
	Thisform.Refresh()
EndIf

After this code (nothing difficult I think), the focus must go to the next control in the tab order, which is a Grid, but the Grid never gets the focus. I think that the focus never leaves the ComboBox.