Uh so, this is what happens in emulator
whats goin on

This is caused by tile randomization. The game swaps out ground tiles randomly so that it doesn't look that uniform.

For custom tilesets just move down everything a few tiles on Map16 in the editor. Those are never randomized.
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GitHub - Kuribo64 - YouTube

Is there an easy way to do that, or do i have to do it all manually?

you'll have to do it manually, i'm afraid, OR, you could just choose a different slot