@artheus11 Hi mate,
I can answer some of your question, for the training camp, you can use training camp six times in a league,
1st time :10 BC
second time: 20 BD
third time:50 BC
fourth time: 100 BC
fifth time:200 BC
sixth time: 500 BC
Question number two if you mean progression then I guess it's training because a player rating doesn't improve in matches but do so in training
For question number three, a player won't recover from a training but rotating your line up every day will help you have full fitness.
For the forth one if you use a Midfielder as striker or Defender as Midfielder, the players won't perform well for sure but if for example you used and center back in a right back position of a center Midfielder in center defensive midfielder it won't have such a bad effect.
fifth one:
I heard that if you have many players from the same nationality, your team will have a better chemistry but I don't know if Fut draft rules applies on OSM too.
For the sixth question, of course you can buy players from the same league maybe from computer by making an offer or buying from other managers which I don't advise you to do
Hope my answers help you
Before saying bye if I did any mistakes answering these questions please tell me,
Bye and thanks,
Fear Force