With Opus 13.22.9, the script column mentioned above now appears to work correctly most of the time. However, scripts that use target_type still fail quite frequently. I haven't found a reliable way to reproduce the issue, but here is a test script along with two examples:
var lst = DOpus.listers.lastactive;
var tab = lst.activetab;
for (var i = 0; i < tab.selected_files.count; i++) {
var item = tab.selected_files(i);
DOpus.Output('item: ' + item);
DOpus.Output('item.metadata.other.target: ' + item.metadata.other.target);
DOpus.Output('item.metadata.other.target_type: ' + item.metadata.other.target_type);
DOpus.Output('item.metadata.other.target_type: ' + (item.metadata.other.target_type == 'url'));
DOpus.Output('');
}