I have created a quick fireshard farming profile. It farms level 45 nodes. Its based north of Camp Drybone at 12, 18 I have had around 1000 Fire Shards in an hour of running completely AFK. On my server there are no other people farming in the area. I have read that maps drop from any node level 40-50 but I have yet found one. they are all included in the loot list but I am unaware if it loots them due to not finding one yet.