How can I edit Layer 1 Overworld Tiles?

[BlackTypoon]

Hi everyone,
This is my first post here, and like every noob I'll start with a question!

My ROM hack keeps the basic Overworld, except from one final twist between the 7th Castle and Bowser's Castle. To do that I've made some changes to Bowser's Valley, and I've learned here how to create Layer 1 Tiles from Layer 2 Tiles, which is very helpful, but I still have one issue.

How to say that... here's the concept:


Don't mind the current map of Bowser's Valley, it's very inaccurate right now.

As you can see, I'm using the Snes logo Layer 1 tiles (originally used in Special World) to create new ones, so I don't mess anything else.
I'd like to know if there is any way to add a road to those customs tiles, like in the picture above, so Mario could walk on them.

Thanks in advance for your answers, and please pardon my poor english, which isn't my native language.

[Maxwell]

It's not possible to have multiple things of the same path. You who have to do a huge amount of ASM and put it in OWASM and personally I don't think it would be worth it.

[BlackTypoon]

It's okay, I've found an other way to get the expected results:
I just edited the tiles for the Back Door and Lava so their background is the same color than the rest of the submap.
Easier than what I was initially trying to do, and same result ^^

Thanks for the answer!