Thanks! Actually, when I have tried to use 2048, he told me that image is too big (2050). So I have found a difference 2050-2048=2 and subtracted it from the image size - this got me 2046. But then Spine reported NullPointerException.

Could you also take a look at this bug: https://github.com/EsotericSoftware/spine-runtimes/issues/478 ?

I am getting a NullPointerException in texture packer. Spine log is attached. I can send you files that result in this error in private, if you need.

Error happens if I am trying to pack one or more 2046x487 images into 2048x2048 atlas (height actually does not matter).