If you are like me, and the last three achievements for watching the ending story, not killing any candles and the unlock all achievements bugged on you, there is a workaround.
Credit goes 我是穷逼只买优惠游戏 on steam who found the solution, and thanks to google translate I was able to figure it out.
Enter properties on the game, go down to Beta and join the "without" door option. The game will need to update and when it does launch the game and go back to level 3. After completing the level you should unlock the achievement for not killing any candles followed by the one for watching the ending story.
If like me, the Kneedle Knight achievement did not unlock, you will need to quit the game, go back to the betas and switch back to normal. Now it will update again, and you just need to enter any level and it should unlock.
This should also work for any other achievements that did not unlock correctly.
Link for the original guide:
https://steamcommunity.com/sharedfiles/filedetails/?id=32453...