I have been running Scrum in several projects. The biggest problem, as I see it, is that not everybody in the organization is into the process. Everybody needs to be committed. Not only the team of developers. Often the managers are the persons that initialize the process and expect that things will change to the better without them doing anything.
My suggestion is that you run a workshop with the whole organization so everybody knows how the process works. Not only the developers. It's essential that you have a person that is really into the process. A person that can answer questions the team and organization have. A mentor.
Being agile is about welcoming change. You should not let the process gets in the way of sense. Do things that works for your organization, but you should try out the whole process before throwing something out.
