there nothing wrong about both injection button enable all the times....if you have install macchanger then you can use injection button (disable) to auto change the mac address....
as for dictionaries you put it on this path....

FAS/diction

there a many dictionaries out there & the best is at 33Gb but sadly it wont fit our beloved n900 due to sized...
but you can download smaller sized or created/edit the dictionaries by putting any word/password you like & save it/compress it as .tar...
my expriences...using John is far more better than dictionaries....