Realtime recording

I'm not sure I follow the problem completely.  When you say it plays back at a different tempo do you mean the track sounds slow or fast with a pitch change like a chipmunk or speaking in slow motion or do you mean it is not in sync with the rest of the song but the pitch is ok.  If it is the former, you are just going to have to rerecord it so it is in sync.  I recommend recording with a click track or a basic drum track to keep you in time and continue to build from there. 

If the timing is right but but it is starting too early or late when you import the track, you can nudge the track by selecting it and use the keypad numbers 4 and 6 to move it left or right in the track view.  Clicking and dragging also works but it can be harder to do if you need to move it just a hair in one direction.