Hi Alvaro.
Well, i fixed only Barcellona and Istanbul (as i'm driving a Cart season and not using F1 tracks): i will send it to you tomorrow, 'cause now i'm not at home; but if you want to try again, here you are how to do. The tracks miss a jam file named tarmac.jam (i found one in Roberto Scandura's Barcellona, but i think there are others in others folder or tracks) so you have to:
1.find the tarmac.jam file
2.copy it in track specific folder
3.open the track with Track Editor, and set the track to use the tarmac.jam
Therefore, you can modify the tarmac.jam with a graphic editor (i use Paint Shop Pro 7) and change the colour.
Otherwise, you have to wait for my email (but i remember, i fixed only a few tracks of excellent Drafi pack).
Claudio