Dragging out an AD component introduces a number of project properties to your flow. They should be populated with something akin to the following:
ADDomainAdminUser and ADDomainAdminPW should be self explanatory. As far as I know, you don't need to qualify the domain user with the domain i.e domain\user or in the format name@domain, but you may have to experiment if you're having problems.
ADDomainName should be a fully qualified domain name, like my.fakename.symantec.net
ADServer should be the IPAddress of the ADmachine
ADServerPort should be the default, 0, unless you've specified a different port.
Hope this helps.