Attached are the 2 AD files you’ll need. Just rename them to .dll (had to change the extension to allow passage through the mail filter).

The AD.Shared component needs to go in the C:\Program Files\Altiris\Workflow Designer\Shared\logicbaselib folder, while the ActiveDirectory.dll should go in C:\Program Files\Altiris\Workflow Designer\Shared\components

One little thing to note here, these are essentially WF 7 components. They will work just fine, but when you deploy the app to your server, you need to include the AD.Shared component, and it needs to be in the BIN folder for your project. What I do is include it in the Project Resources so it gets published every time you publish your app: