Here's the custom edits I've done:
It looks great, but wherever you uploaded it or however you did it, it didn't preserve the .png transparency of the background, so it's a bit hard to use. I especially love the barren ashland trees (...or at least I assume it's ashland), and the snowless mountain. For some reason the volcano one also appeals to me more than the older ones, I think it's the darker aesthetic.
Edit: By the way, having two mirrored ports is completely unnecessary. You can flip tiles by pressing x, so you only ever need a left- or right-facing tile, and then you can flip them on placement if needed. :)
I actually just discovered the tile-flipping option the other day haha. I just uploaded the image as I had made it before the discovery.
Unsure what happened with the transparency, but I'll see what I can do!
Transparency should be working with this one. I didn't bother deleting the redundant port, though.