在单（大）SQL查询语法中使用CASE语句作为COUNT函数的前身

I'm having trouble incorporating a bit of logic into a large SQL query. I'm using SQL Server Reporting Services 2005 with the Report Designer, and it only gives you one area to define a single SQL query to populate the report with. Hopefully someone can tell me what's wrong with my syntax so I can get it running.I'm having trouble incorporating a bit of logic