right lelle...
you need to check your pallette usage over time... (frame to frame)
You've got some dark greys in there somewhere that on frame 11 -are starting to creep into the dissapation sequence... this is the right thing to do - but you need to carry on with it through the remaining frames - so by the end of the sequence you've kind of cross faded totally from the yellow/red hues to the grey ones... but in order to do this you'll need to manipulate the pallette somewhat and add a couple more greys or consolidate the pallette down and edit the sequence accordingly. (these colors appear brielfy on frames 6 and 7 too) - if you use them then be consistent across the sequence.
Also, your pallete zero (transparency color) - when you next set your pallette up - should be a vivid color sayt bright magenta or green - any color that you're not likely to place into the main piece of art by mistake - in this case you've got orange background and there are a few stray pixels in there that I don't think you meant to use... simple mistake, easy to rectify...
Other than that... nearly there... keep it up... I'm off for the w/e now so over and out... I'll check back monday.