Thx Emre.
Version 7.2 is definitely the way to go and I'm planning RC3 for tomorrow.
1. Sorting subtasks below their respective parent task is much improved
2. I will be adding a kanban preference to indent subtasks for better readability
3. Editing of task titles is fixed (7.1.5 requires 'F2' to edit labels)
4. Sorting (which also works in 7.1.5) is via the main application menu and applies to all Kanban column
5. I don't have plans to support manual reordering because manual reordering and sorting never play well together in my experience.