CRM can be challenging to troubleshoot with log files scattered across several servers and often underlying problems that don't even appear in the logs. I stumbled upon this diagnostic tool that was helpful in finding the problem with an SRS install. Enjoy!
http://blogs.msdn.com/benlec/archive/2008/03/04/crmdiagtool4-for-microsoft-crm-4-0-has-been-released.aspx