(update September 2018): Campfire has been udpated to v1.12.1 for bug fixes and to optionally support SKSE64 and SkyUI SE.
It’s also perfectly fine to disable Frostfall using Options: Frostfall spell until an update. Campfire and Frostfall work great without SKSE64, so players having yet to try SKSE64 may choose to wait for proper updates. Here I’ll review the steps and reasons for a workaround. Over on Nexusmods, there’s been a number of players asking for help with getting Frostfall and Campfire working on Skyrim Special Edition with SKSE64 and SkyUI SE along with several other players offering tips. Skyrim Frostfall and Survival Armor Edit for Warmth Show Your Tail With Campfire Cloak In Skyrim Skyrim SE - XPMSSE: Modify Weapon Positions Convert Black Sacrament Armor to SE Step-by-Step