Problems when playing Planning Poker.

We played Planning Poker for the 1st time and I experienced the following situations.
But It was really great. I think that does the purpose. I will try to find the answers for the following problems I faced and post them in the blog..


1. When Moderator reads 1 story we kept playing Poker and came out of an estimation to that specific story., But when we went through the PB more and more., team wanted to revise the previous story estimates again as its a comparative thing., How do you handle this situation?
Do you get the team to analyze the PB before coming to Planning poker so they will be more or less accurate with their comparative guess with other user stories in the rest of the product backlog?

2.There was one user story which we had to purchase some device for that. Scrum master ask where do we do the procurement management planning, Cost estimation etc, Will SCRUM has some guidelines for
procurement management for the project.

3. Customer who acted as the product owner didnt have answers for some of the questions.. there were situations such as I need to check with my infrastructure guys.. I need to ask my BI manager etc. How do you tackle that situation?

4. for certain stories we felt that we need the use cases or further analysis before thinking of their weight. ..

5. Looking at from the Project Office I saw many team for many projects they had different type of assessments. As an Example., same story "User needs to log in to the site and fill the registration
form" was rated by the Team A as 5 and Team B as 20.. so how do I compare and see each team performance from the top when I look at my teams product burn down charts?