Should we worry?

Remember the new A frames that went in in the spring?

We just noticed a large crack under one of them

You can see it in the shadow just to the right of th cables coming down in the the electricity box. It would seem that the front wall has moved away from the internal wall slightly.

The roofer came to look at it, and says that it is ok and is just settling a bit under the new weight. He and Doug marked it in various ways so we can watch to see if it is getting any worse. 

We are not sure when it appeared as Doug just noticed it the other day. Generally I try not to look at the walls or anything else for that matter as the number of spiders webs and the amount of dust just traumatises me - or the amount of work that whatever it is needs...