Questions about the 08er Impreza with LPG

Bonjour Since I recently ordered a new Impreza with LPG system I still have some more concrete questions, which the dealer could not answer me exactly. As far as I know, the warranty for the engine intervenes, if the LPG operation is to cause damage. But are there certain exceptions? In the warranty regulation I found nothing special. Are special measures taken to make the gas operation safe? If so which e.g. only hardened valves? Is the This means that it makes sense to use Flash-Lube or not at Impreza? Where is the gas filling nozzle installed? When I asked the dealer, he said that one had not yet converted an 08 Impreza and that one had to wait for the documents and plans of Subaru, because it is there. Can one determine the installation side as customer, if it is placed on the fender? The dealer said that the engine sounded a little different with LPG. Is that true? THX Greetings, Heron