I've being trying to use that guide you pointed, but I'm having problems in constructing the prompt answer XML file for the parameter %SELECTION%. I need to select several options in the InfoObject options. When i use single selections parameters if works perfectly. But, it seems that BPC isn't accepting the format of my XML. It passes the validations, but when the package runs this is the resulting log:
Im trying to use the attached XML file (and lots of variations of it).
Thank You,