When using the select_*_from_file with a GeoJson file, the values read using calculate work for in other columns like relevant, but don't let the extracted value be able to be used as the default value for a survey question.
My example is I'm extracting data for a region from OSM, think all restaurants. It I read the label from the data file, and I know it's been read since it works elsewhere, it doesn't work in the default column. If it did, I could populate the default value for each survey question based on what's in OSM now, and truly edit those values. For example, you're eating a remote restaurant, and in OSM, all it has is "amenity=restaurant". And you want to add "cuisine=pizza". What cuisine the restaurant serves is already a survey question, so it'd be nice to have pizza as the default, so the mapper would ignore that and go onto the next question. This would truly enable editing OSM data with ODK Collect, a long-time goal.
Right now the OSM values do wind up in the output file, but then I have to conflate any changes from the mapper with what's in OSM. Here's a simple test case and datafile: https://www.senecass.com/HOT/test.zip