I am using OpenStudio's RadianceMeasure with two identical files. fail.osm here creates two WG1s in mapping.rad causing the RadianceMeasure to fail. The idential success.osm here doesn't fail.

I have tried it on both a Linux of OpenStudio 2.5 and a Windows installation of OpenStudio 2.4 with the same fail/success result. If I simply run the fail.osm multiple times, without changing it at all, it will eventually succeed. In fact, that's how I created success.osm.

My guess is that something about the file-saving that happens when you run a file in the OpenStudio App is putting something in the created subfolders that eventually gets the failed version it to succeed. Or, maybe the file-saving gets rid of some special character hiding in the OSM text?