Yes, AD logons can be used to run the service. The service has to be properly installed for the AD user from within CRD following the instructions in Demo 29 at http://www.christiansteven.com/crd/demos/crd_demos.htm and in the help file.
All the demonstration shows me is how to enter the info. I use the actual Windows Services console to manage this service instead of the CRD GUI. The problem is, is that when I add a AD User the scheduler does not execute the reports.
Also I opened the CRD GUI for the NT service and the old user name and password is set up already and it will not let me change the parameters. When I go to change then the OK button greys out so I cannot click on it after I make the changes.