Found another on Stage 6. If you walk to the right (metal gate where the humans introduce) and keep walking, it plays the intro again after exploring the stage. Here is the save.
i remember in stage 5 the tentacle barrel room key is from the goblin with the masked orc, but it looks like it doesn't drop the key anymore. The save is when the orc and goblin are on the way to Lily's room for easy testing.
