Error integrating sales document

I am not able to create sales documents in version 10 of ERP Primavera using the engines. I'm getting an error invoking the Actualiza method:

  

Unable to save document. 0-The best overloaded method match for   'double.Parse (string)' has some invalid arguments

Using the example provided in github the error is the same

  

link

Thisistheeventwheretheerrorisbeinggenerated:

PriEngine.Engine.Vendas.Documentos.Actualiza(invoice,refstrAvisos);

Code

privatevoidCmdSave_Click(objectsender,EventArgse){VndBEDocumentoVendainvoice=newVndBEDocumentoVenda();stringstrAvisos=string.Empty;invoice.Tipodoc=txtTipoDoc.Text;invoice.Entidade=txtEntidade.Text;invoice.TipoEntidade="C";
    invoice.Serie = txtSerie.Text;

    // To save the document as draft set this flag to true
    //invoice.Rascunho = true ;

    try
    {
        if (checkBox1.Checked)
        {
            // Set all the entity related information.
            PriEngine.Engine.Vendas.Documentos.PreencheDadosRelacionados(invoice);
        }

        if (listView1.Items.Count > 0)
        {
            foreach (ListViewItem item in listView1.Items)
            {
                VndBELinhasDocumentoVenda linhas = new VndBELinhasDocumentoVenda();

                double qtd = Convert.ToDouble(item.SubItems[1].Text);

                // Add new line to the invoice and set all the item related information.
                PriEngine.Engine.Vendas.Documentos.AdicionaLinha(invoice, item.SubItems[0].Text, ref qtd);

                linhas = invoice.Linhas;
                linhas.GetEdita(1).Desconto1 = 10;
            }

            if (txtobs.Text.Length > 0)
            {
                PriEngine.Engine.Vendas.Documentos.AdicionaLinhaEspecial(invoice, vdTipoLinhaEspecial.vdLinha_Comentario, 0, txtobs.Text);
            }
        }
        else
        {
            MessageBox.Show("There are no items.");
        }

        PriEngine.Engine.Vendas.Documentos.CalculaValoresTotais(invoice);

        // Save the document as draft.
        // PriEngine.Engine.Comercial.Vendas.ActualizaRascunho(invoice, ref strAvisos);

        PriEngine.Engine.Vendas.Documentos.Actualiza(invoice, ref strAvisos);

        if (strAvisos.Length > 0)
        {
            MessageBox.Show("Error writing document. \n" + strAvisos);
        }
        else
        {
            MessageBox.Show("Document saved with success.");
        }

    }
    catch (Exception ex)
    {
        MessageBox.Show("Unable to save document. \n" + ex.Message);
    }
}