Hi Benjamin,
assuming you did create the implementation and activated it, the next step should be to set the filter properly. This BADI needs a filter option to be called.
Set Value1 with your Smartforms Object and check if it is called.
Ps.:
You don't need to replace, just create another implementation like I did, ZTEST below.
But this BADI doesn't allow multiple implementations with the same filter, so each implementation will be called for its own form name.
Regards,
Frisoni

