[Markus Heinsohn]

OK, I tested this in OOTP 15 with a fictional league created for 2014 and it works well. In the league setup, options tab, you can check to box to import historical rookies and the box about rookies being from random eras. Then when you progress, the real rrokies get imported.

The problem with the 2014 real roster set is though, that this does not work because the league already includes all the real players from history as retired players, so importing again would result in duplicate players.

Edit: You can work around this in the 2014 roster set by creating the game and then going to the retired players listing (History screen, players tab, retired player sub tab), click on the mass select box in the upper left corner of the player list, then right-click on a player and select "Delete"... this will delete all retired players and from now on the game will import rookies from random eras.