I'm not sure if this one's even mine. I'm sure I made a close port of the original Emerald Coast from Xmas 0.96, then an improved Emerald Coast, then an Emerald Coast for Adventure mode.
I know there's one Jackel made, and I've heard of JTE messing with Emerald Coast.
I could try looking through my files though. However, seeing as this was three years ago, I doubt I'd have much success.
Edit: Oh, wait, yeah, this one's mine. I thought the music sounded familiar. And I found the other two versions too!
As for the REDWALL, that's because 1.09.3's srb2.srb probably doesn't have those textures anymore in its TEXTURE1 lump (though I can't fathom the reason why they'd work in 1.08, as I don't think they were entries in 1.08's TEXTURE1 lump either). I can fix these up really quickly.
If you find any other discrepancies (like no death pits in water), that's what the original level was like. This is only a close-to-direct-as-possible port from the Emerald Coast of XMAS v0.96. As I said, I made a retouched version.