Automatic Change detection is not supported in TD current release. So you need to schedule the task manually.
In TD v1.5, I noticed the ...\etc\discovery_util directory which contains files to assist execution outside of the discovery console. I don't see any mention of this in the documentation so I am assuming this is unsupported.
I tried briefly on a test installation and somehow made it so I can no longer run discovery jobs (keeps waiting on query to retrieve discovery info). I will play around a bit more over the next week or so. I'll keep you posted.
If you try and figure it out, please let me know.
On the notion of auto-creation of domains, it may be worth a direct query against the TD database (unsupported for sure). If you can put the query results in your job xml file from the discovery_util directory noted above, you're in good shape.