Hi Ladislao,
You can add manually the customer number in the table V_AISAPCUSTNOS, with this when you run the report, this will use the SM_SP_XXXXXX RFC form the customer to bring all the information from the market place..
Remember to add in the SMSY_SETUP --> Expert Settings the field "Generate BP from OSS"=C and Generate systems from OSS =N (Page 20 from the VAR Guide)
The best picture for understand the logic:
Have fun!!!
@WenSolman