What program did you use for making the sprite sheet? The autotile pattern within gms2 doesn't line up with the tile sheet. I thought I was messing up somewhere until I realized the demo tiles were in a different pattern.
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I mean built in auto-tile pattern in gamemaker; The template it uses doesn't match with your example tile set. your example has the last tiles swapped around.
The scripts I use for tile creation follow the order used in gamemaker. So using them as is, messes up the auto tile scripts. I have to rearrange the tile order exactly like yours for it to work correctly.