Using Aseprite v1.3-rc6-x64, tiling does not work at all regardless of whether "Force tiling" is checked or not.
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I'm not able to test on rc6 without building from source. I assume you have tried this but just to confirm - tiling only really works with even brush sizes. If tiling is not otherwise working I am not sure what to tell you since all the extension is doing is creating a new variant of the built-in custom brush feature. I will investigate this further once I have rc6.