Hi Riccardo / Robin,
Which SP are you having on 4.1? Please follow http://help.sap.com/businessobject/product_guides/sbo41/en/sbo41sp3_cr_restws_en.pdf - Chp 3.5 and you should be able to pass parameters to Crystal RESTful services. I see the initial query that you have gone through some of the pdfs for achieving this - however, can you once again confirm that you have followed the steps mentioned in the pdf?
Regards
Sumitesh
