Steph,
For Openstudio-related questions, you are much better off asking them on
unmethours.com since the developers are actually on it everyday.
Long story short, the numbers are stored in the SQL file, so you need to query it.
As far as BDSF goes, there's a new field in the OS app for Window Materials called "Window Glass Spectral Data Set Name, but I haven't used it yet. And as previously, you can always use an EnergyPlus measure to add your BDSF constructions to your osm file prior to running E+.