Is it possible to use the editor to edit players in the game at any time during the season and edit each attribute & rate of growth and such? If yes, how could this be done?
You cant use the football manager data editor for 'live editing' but you can download FMRTE. this will let you change almost anything from club reputation to contracts and attributes etc
You can change in-game stats although you must make sure the CA/PA are good enough to enable the stats to stick (don't give a really low CA/PA and then give him 20 for finishing, pace etc etc)