- There's currently no way to define the number of columns/rows, and it's very unlikely we'll add this feature. Read on.
- If your animations don't fit into a single sprite sheet, it's very likely your runtime (game engine, framework) won't be able to display them either. You Again, read on 🙂
Why are you exporting to a sprite sheet? You lose essentially all Spine features at runtime this way, and you run into problem 2 a lot, especially if you use big image attachments.
What game engine/framework are you using? We have a multitude of runtimes to support the most common engines.