Hi NoGi
I battled with this for a while - and the crystal report was so complex and took so long to load through the client that I gave up on it. I eventually got the clever people to build a simple URL that pulls information from the ITBM database and presents the RFCs in a calendar view. I have one for the Forward Schedule of Change, and then one based only on planned downtime. Doing it this way had the added bonus of being available on the intranet, rather than through the Service Desk client / Service Portal so people do not have to be logged in to have access to the schedule.
I think this is an area where Service Desk product can expand to add even more value.