In a Live Effect, a kRasterArt element, which is a raster of a single spot color, loses color information between kSelectorAIEditLiveEffectParameters and kSelectorAIGoLiveEffect.
This especially becomes a problem when removing the Effect from the element.
Reproducible steps:
1. Rasterize an element with a spot fill, no stroke
2. Apply 'Outer Glow' Effect
3. Save, close, and reopen the document
4. Remove 'Outer Glow' Effect

I've copied the TwirlFilter sample code from the 2024 SDK, called it TestFilter and simplified the code. It has only been built and run on macOS.
It demonstrates the color loss between these 2 selectors through message dialogs in the EditLiveEffectParameters and GoLiveEffect methods.
It is available if needed.