I know that the SQL Server 2000 Query Analyzer can be used to debug stored procedure but I've not tried to debug a trigger. Try creating a stored procedure to insert a row into the table and then trace it. Maybe the QA will trace through the trigger.

On another note, are you sure that you want to instantiate the File Scripting object for every insert, update, and delete against the table. This is sure to affect performance.

-Mike