Store Business Documents on WD ABAP - Travel

Hi experts,

We are using SAP Portal 7 with BP 1.4 and ECC EHP4 for SAP Travel Management. On WD ABAP for travel management I don't find configuration to store business document on GOS services. This option is available on backend on PR05:

On the portal I can't see this option available:

We are studying with our external content provider the possibility so save a business document but I guess SAP standard does not deliver the possibility to store and open these documents through WD ABAP for travel management.

Would it be difficult to integrate this feature on the standard WD ABAP?

Thanks in advance.

Best Regards,
AS