The True Track is Atlas' "roadbed track", but the track and ties are actually sectional track ("Snap Track") that can be removed from the roadbed.
Gil - is it the ties and rail that are coming loose, or just the rails (i.e. rails separating from the ties)?
If it is just the rails, I would suggest that the turnouts are defective and you should return them to wherever you got them. If this is not possible, you can glue them back down to the ties with an epoxy-type glue, making sure they are in gauge when you do so.
If it is the rails AND ties that are lifting from the roadbed, make sure the turnout is not being flexed or warped as Scoobie says - the turnout should lie flat.
Hope that helps.
Andrew