Same all Gacha Art APKs i've tried they all say to update Gacha Club. i think it may work if you remove Gacha Club, but i didn't tried because i don't wanna loose everything on it.
You can save your characters using offline exporting and importing, also I know a way to fix this and have separate gacha mods(I have 14 gacha mods installed currently including gacha art) but you'll have to download some app so that you can alter the game's files and make it so that you can have separate gacha mods so it's a bit complicated but i'll tell you if you want to know though :P