Might be, it is an example that comes with DB so I’m not sure how it is done.
I have tried with a different one and it simply works:
It has some minor issues but I would say it is completely usable. At least I will use it for my games.
With this spine file, I can’t see the images on the editor and only when the game is running:
If anyone of the Defold Team wants to check why this is happening, here are the files
demonanim.zip (2.0 MB)
Leaving that aside, it works surprisingly fine 