@IndieDoroid At first I was a bit confused since you said SRP which usually stands for Scriptable Render Pipeline, but I assume by SRP you meant Standard Render Pipeline.

Anyway, unfortunately I could not reproduce the issue in Unity 2020.3 when either using the URP 3D or 2D renderer by assigning the provided Example URP Asset or Example 2D URP Asset as Render Pipeline Asset. Everything was rendered as expected. Which Unity version are you using?

IndieDoroid Because on the main project, whenever I re-import the libraries I always get warning pop ups saying some spine example files being version 4.0 and weren't imported correctly. (because I updated all the spine files and runtimes to version 4.1)

Then I assume that you then did not cleanly remove the 4.0 runtime before installing the 4.1 runtime (as described here), and thus have some leftover 4.0 files remaining which trigger the warning. Unless you have modifed the spine-unity runtime files, I would recommend removing your potentially "mixed" 4.0 / 4.1 runtime again and installing the latest version of the 4.1 runtime cleanly. As always, backup your project first, just in case anything goes wrong or if you forgot about some modifications you did to the runtime.

@IndieDoroid Glad to hear you've figured it out, thanks for getting back to us!

@IndieDoroid SkeletonGhost spawns GameObjects programmatically here, then sets the GameObject's hide flags to hide them in the hierarchy here. So you just need to change the layer of the hidden spawned ghost GameObjects accordingly.

IndieDoroid If I hack this script, will it get overridden when a new Spine runtime is installed? -- I guess the fix is to use and save a different iteration of the script.

If you modify the original script, then yes, you might accidentally override your changes. You could however easily just create a copy of this example script (named differently) an adjust it to your needs. The scripts in the Spine.Unity.Examples namespace are as reference for your own implementation. They are not a generic solution which covers all use cases.

IndieDoroid I also changed this. Hopefully that doesn't do anything nasty to the script.
const HideFlags GhostHideFlags = HideFlags.None;

It will just no longer hide it in the hierarchy, as the name implies.

Just out of curiosity, what is the benefit of using the HideFlags variable\const? .. from what I can see, it just makes it harder to debug the hierarchy

This line is for hiding the many ghost renderer instances (10 per skeleton ghost) in the hierarchy. Otherwise it would be cluttering the hierarchy window with lots of entries.

IndieDoroid Also I read online that getcomponent() isn't suggested to be run at runtime? Best to keep it in Awake()\Start()? Is it ok to keep running all the time?
pool[i] = go.GetComponent<SkeletonGhostRenderer>()

I use the ghost script whenever a power up is used, which is frequently.

oh nevermind, it doesn't get run all the time! got confused..

Yes, it's run only in Start. In general it's only an example component, if you dislike anything, please change it accordingly (in your own copy of the script).

IndieDoroid I had to also make a copy of SkeletonGhostRenderer.cs it seems.

I don't see why that is necessary, but you might have your reasons .

IndieDoroid Now that you mention this.. I can see the benefits of it. I'm going to figure out how to incorporate this into my other scripts.
Now that you mention this.. I can see the benefits of it. I'm going to figure out how to incorporate this into my other scripts.

Thanks for the help Harald!

Glad it helped.

Glad to hear you've figured it out, thanks for letting us know!