I cleared Microsoft Dynamics CRM 4.0 Customization & Configuration Exam (MB2-631) last month. It appears to me that this exam is much easier than the Application one (MB2-632). As long as you have done some customization work and you are familiar enough with the textbook (Course 8912), you should be fine to pass the exam.
The following are a few tips for this exam:
- Understand the relationship between security role and business unit. You should also have the basic idea about the security model of Dynamics CRM 4.0 application.
- Know how the default currency works when you create record (Page 4-40).
- Understand very well 1:N, N:N relationship, it's very important to be able to identify the primary entity in a 1:N relationship.
- Know the different cascading options when you create a 1:N relationship.
Please excuse me for the incomplete list. It's been quite long time since my test, I can hardly remember anything from the exam. Hope this helps a bit. My advice for the exam is, take it as a motivation to refresh all your knowledge about CRM application, not just to pursue another title on your business card. Passing the exam is pretty easy, getting your skill and knowledge updated is actually more important than passing the exam itself.