Spine 4.3.14 export won't load in UE5.5.4

Vein

I'm using UE 5.5.4 with the spine-runtimes-4.3-beta plugin, and exported data from Spine 4.3.14-beta.
However, when importing the .skel, .atlas, and .png files into UE5, I get this error:

Couldn't load skeleton data and/or atlas. Please ensure the version of your exported data matches your runtime version.

The filenames match, and I’ve confirmed that both the plugin and the exported data are version 4.3.
Is there something else I might be missing?

Thanks in advance for any help!

Spinebot

It seems like you are experiencing an issue with importing Spine 4.3.14-beta exported data into Unreal Engine 5.5.4 using the spine-runtimes-4.3-beta plugin. The error message suggests a version mismatch, but since you've confirmed that both the plugin and the exported data are version 4.3, the issue might be related to the file naming convention or a specific setting during export. Make sure that your asset files do not share a common prefix, as this can cause issues in Unreal Engine 5.3 and later. For example, if your files are named skeleton.skel and skeleton.atlas, try renaming them to skeleton-data.skel and skeleton.atlas. Additionally, ensure that the "Premultiply alpha" setting is not enabled in the texture packer settings, as this is not supported by the spine-ue4 runtime.

ExNull-Tyelor

We had a similar issue a few weeks ago.

Since the v4.3 Editor is still in beta, it means that not all runtimes might be updated to support v4.3 exports yet. This issue sounds exactly like the one we ran into, except in Unreal rather than Unity.

I recommend you use v4.2 until v4.3 is released out of beta, since that will ensure your exports and imports all work properly from the Editor to the Engine.

Vein

ExNull-Tyelor
Thank you for your reply.
I'll try again with v4.2 for UE5 later as you suggested.
As for Unity, Spine 4.3.14-beta is working correctly, but with 4.3.15-beta and 4.3.16-beta, it seems the physics constraints are not yet reflected in the runtime.

Mario

The runtime changes in 4.3 are pretty big and still in flux. As such, porting from the reference implementation (libGDX) to C, C++, etc. will only happen once the reference implementation has stabilized.

Vein

Mario
Thank you for the clarification.
That makes sense regarding the runtime changes in 4.3 still being in flux.
For now, I’ve exported my character using Spine Editor 4.2 and imported it into UE5. While the .atlas and .png import correctly and generate the expected assets, the .skel file doesn’t create the skeleton asset, even though there’s no import error.

Misaki

Vein Make sure that the prefixes of the .atlas and .skel files are different. This is a required step for using UE 5.3 and later versions. For more details, please refer to the following section in the documentation:
https://esotericsoftware.com/spine-ue#Updating-to-Unreal-Engine-5.3-

Vein

Misaki
Thank you! I was able to successfully import the character into UE5.5.4 after following the note about different prefixes for .skel and .atlas files.
That was indeed the issue. Everything is working now!