For the permissions problem, make sure you have select privilege on view server state...here's some info on that:

from:

http://www.codeproject.com/KB/database/Dynamic_Management_Views.aspx

To query a server scoped DMV, the database user must have SELECT privilege on VIEW SERVER STATE and for database scoped DMV, the user must have SELECT privilege on VIEW DATABASE STATE.

GRANT VIEW SERVER STATE to

GRANT VIEW DATABASE STATE to