Problems with Animated GIFS

I spent some of today making a nifty new animated GIF thingie for use as an LJ icon. but after I saved the individual 'tweaked' pics to take them into Animation Shop I realised that 1 of the pics was darker than the rest as I'd done something to it that I hadn't done to the others. So I had to go back and open the others only to be reminded that saving as .TIF merges all layers and that I'd have to start over! Arrgghhh, I really need to learn how to set up Macros in PSP.