Yes, it's still supported and works with the latest version.
Glad you were able to figure it out! This is actually the only way to do it - I never was able to implement anything on the topic row level, as I couldn't do it generically and have it work automatically with all content items. It would have required manual template edits.
As for the label and fieldKey.... you can do that as
{$row->template_fieldKey}
So for example, if you have a field with a key "field1", it would be $row->template_field1. You would do the label like
{$row->template_fieldKey_label}
Hope this helps.