Hi Fabio,
We are currently rebuilding our automatic integration from BW Cube for data that comes from a non-SAP system. We have some lessons learned we may be able to help you with. We have attempted the ECC integration but hope to soon. There is a small but active group of SuPM users that you should definately connect with. We have started a ASUG Influence Council and also hold regular calls for exchange of best practices.
What SP level are you implementing now?