(http://www.buzzerbeater.com/community/forum/read.aspx?thr...)Training guide is here.
Training takes place once a week. You can change it all you want, but you will train with whatever is selected at the time training occurs (around 6:00 AM EST on Friday.
Training single position does go faster. But training 1v1 is recommended for young players because it raises 3 skills (HAN, DRV and JS).
Main thing is your players need tom play 48 minutes to get full training. A lot of the other stuff should be explained in the thread.