I'm glad you found a workaround! The canvas size shouldn't matter; it would just take longer to calculate.
However, you mentioned using tilemaps. In case you're using Aseprite's built-in Tilemap layers, that seems to be the cause of the crash. I have had this on my to-do list for my other plugin, but I haven't gotten around to looking into it yet.
I will put it as a disclaimer into the description :)