But, REMEMBER, that GIF-optimization breaks palette make it non-'UNI-palette'. Because of it - assembled GIF-animation from these optimizated files can contain frames with different palettes (because optimization) will have bigger size (with every frame will be saved it's individual 1 KByte palette, which different from other frame's palettes). Animation from 50 these frames - will have size bigger on 50 KBytes in comparison with animation with non-optimized frames, which have identical UNI-palette) (in detail - read help chapter 'GIF-animation').