I suppose late is better than never.
DBH is Diameter at Breast Height.
It was part of an ongoing discussion on the import mailing list and has since been converted to circumference.
These nodes will be deleted and replaced with the proper ones.

Where these nodes added by accident?

There's a service road that comes from the intersection. I've now added it but I'm just going off memory of where it goes.

Thanks for the correction, must've missed it while reading that page. If I'm understanding you correctly, you may be interested in seeing the indoor map of the building.
http://openlevelup.net/?lat=45.348361&lon=-75.755665&z=19&t=0&lvl=0&tcd=1&urd=0&bdg=0&pic=0&nte=0&ilv=0