I think you are talking about the "ghost" laps, From the first f1rs
screen choose to race in time attack mode, then go to the time attack
screen and click on the type button, and make sure ghost is selected,
not free run.
Go to the track and start driving, then when you have done at least
one full lap, and you have a good lap that you want to race against,
simply exit the session (after you have passed the start/finish
line!) by pressing escape, then choosing exit.
You will then be back at the time attack screen that has the ghost
button (bottom left), click on this and select the time you want to
race against by ckicking on it, it should then be highlighted.
Then go back into a time attack session, and your ghost car will be
waiting to race you as you pass the start/finish line for the first
time.
If I have misunderstood you, and you are actually talking about
replays, AFAIK you cannot replay time attack or training sessions,
you can only replay actual race sessions. (I think?) and to do that
you must have selected replays in the configuration screen.
8?)
*Peter* 8-)