Image 1 - a blur effect rendering correctly (the color of the glow stays pink).
Image 2 - the same blur effect applied to different illustration within the same file but on different layer. It does not render correctly, as You can see (white instead of pink)
Image 3 - both these elements copied to third layer within the same file and they both render correctly.
Image 4 - the same element as in Image 3, copied to the layer where it doesn't render correctly
QUESTION: what's going on?