I've also confirmed the issue. It appears this may be a limitation with the Grid, rather than the interface itself - I'm thinking an option to sort by sortkey(programatically looking for columns with the same name as the expected column, but appended with _sortkey) would be the way to go. Looking into how to implement this now.
I've also confirmed the issue. It appears this may be a limitation with the Grid, rather than the interface itself - I'm thinking an option to sort by sortkey( programatically looking for columns with the same name as the expected column, but appended with _sortkey) would be the way to go. Looking into how to implement this now.