I am thinking about getting a Thule Playpen or maybe a large gear box to attach to my dealer-installed roof rack. But I am curious if either of these items block the sunroof in any way. Can anyone comment? Thanks.

I can let you know later tonight or tomorrow. Getting ready to install my playpen for a trip to Florida this week.

Here is the basket in relation to the sunroof. I hope this helps.
http://www.digitalpose.com/mbr/1/17578/p/325033_5239949274912282329_v.jpg

That's excellent. Thanks a lot for posting that picture. It answers my question perfectly!