Thanks, Joe. I fixed the bugs in the Dam that you found.
The bugs with Lake Hylia aren't bugs, actually. For one, I have
no idea how you got to those Whirlpools, but those are the "Pre-Flood" Whirlpools. They don't lead to warps at all. We're not even supposed to be able to swim in that water before the flood. So I took out the whirlpools entirely. Should solve that little problem.
But that should also indicate to you that you're not supposed to be able to get that HCP that you saw, high up on the cliff, until the Dam floods. You can just swim up and get it then. So yeah, ... do.
Oh, those Magic Shop scenes are actually what was on Screen 80. Screen 80 is the default screen that you visit for when a warp doesn't lead anywhere, like those whirlpools. They didn't have a warp attributed to them, (Because they weren't supposed do, as you couldn't reach them at that time in the game's plot.) so they led to that default room, which happened to be a witch's shop. Nothing actually takes place in that room. It's just a placeholder / template for use when the designer is too lazy to make a new room for each kind of house or shop or whatever they want to use.
So yeah, no bugs in Lake Hylia. I just removed the whirlpools. They'll be back when it floods.

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Ah, those Kanavas bugs. They're more like visual Glitches. C-Dawg decided to use layering like that, I guess. No worries. I'll fix 'em.