Being able to include Tilemaps on Families would help a lot especially regarding collision aspects, and personally, it would help my game immensely! Just a quick suggestion to the devs for the future.
Thanks for the tool, I've been enjoying it greatly since I bought it!
You can already add a Tilemap to a family.
You might be trying to add a Tilemap to a family of a different Object Type. You can't have different objects types in the same family.
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