You can still make a player stop on one skill point before next star. The thing you can't do is continue to train them and not post the skill gains. Why would you want to do that anyway? They will be lost. Just stop training or playing them and they will remain on the negotiation market.
To manage where the skills go, go to your player and click on the skill area that you want to focus on. Your gains will go there. I don't have a player with special skill training now so can someone confirm that you can choose special skill training to receive the new skill points?