Actually using the "subject" for Dewey is quite good (now that it is working). Grouping by "#subject" displays the ten top level Dewey Categories e.g.
-------------------
1
100PhilosophyPsychology
2
200Religion
3
300AnthropologySociology....
5
500Science
-------------------
I can then select the top level Dewey class that I want (e.g. 5 Science),
[See Screen shot 1]
which then displays a scrollable list of all the sub classifications e.g.
512 Algebra
515 Calculus
[See Screen Shot 2]
So I am happy with that ! I will post a screen print when I can co-ordinate my fingers. At the moment I either change the volume or turn it off (Strange way to enable screen print ...)
Edit1 - Uploaded screenshots taken wth crappy mobile phone camera. Still cant use built in facility
Edit2 - Took cover off - still difficult to take screenshots.