Hi Joe, Firstly, thank so very much for explaining your problem Joe. I know myself how frustrating it is when software ( especially Blender ! :) ) doesn't do what you want it to do.
I didn't realise that the size of your original sprites when calculated in Animshed were going over it's limits. Software has to have some limits and I didn't think anyone would exceed them beyond a sprite sheet of 3000 X 3000 pixels.
At lease your get around ( although not ideal ) is that you only have to resize one sprite and not all of them and Animshed resizes the rest to fit.
On the next update I will consider putting in an option for Animshed to adjust the sprites to fit should the calculations take it beyond it's limits.
Thanks once again for your feedback Joe.
Interested to see what your big animations are. :)
David