You're right it doesn't handle column permissions, the code is iterating through by object type and then for each object (table,view, stored procedure, function) executing the ListPermissions method. It looks like column is another object in SQL-DMO. I'm currently working on a Powershell script which uses SMO, once its finished I'll write an article about it. The Powershell/SMO script will handle column permissions correctly.

--Chad