Preferences text file, and bug on 0021

I learnt how to edit the preferences.txt in order to provide a useful window size for code (default.window.width and default.window.height) in version 0019 (my first experience of Arduino). I updated to 0021, which uses the same preferences file, but it won't take any notice of the sizes specified in the preferences file.

*Is this a bug in 0021 ** ?

Also I agree with other forum users that a full explanation of all the editable parameters should be available as most are quite obscure to me (and, I suspect, to many others).

*** Please, Messrs Banzi, Cuartielles, et al, could you do this ? ***