From the manual, it sounds as if it will let you reload the 150 PD/FD channels, but it sounds like for some reason it won't let you get the race channels back.
The latest arc83/84 has a web import capture which will import directly from a web page It works ok but you have to be careful so that you get all the freqs.
is there a particular reason you want to get those frequencies back? side note: Load83 is free if join the pro83 yahoo group. for free software, no complaints here.