Whenever I'm there, I stay at the Kyriad Prestige, within the airport premises, about 5 min walk from FSI. Thats probably the closest you'll get to the training centre. FSi rates should apply when you are staying there i.e 89 Euro's per night. To get from CDG to le Bourget, jump on the RER B train at CDG straight to le bourget station, from there you need to take a taxi to the hotel. Enjoy the free hot drinks at FSI.