Do NOT use the receivers switched outlet for the sub. Find another way to get it in there. Switch it with yor CD player or something but you are really taking a chance on damaging your receiver by plugging an AMP into it.
The auto on will make the sub turn on when it see's a signal and will...
What kind of entertainment center is that? It looks nice. I've been looking for something like that to house my stuff but it can't be huge. I don't know how big yours is but it looks nice from what I could see in the pics.