Let's start with something simple.
Many sprites have bottom part not drawn good enough to be naked because it had always dress drawing in front of that. It would be good to improve that drawings little bit.
Let's start with drawing tool aspect of it. You can either use something that can decompile Flash and update that inside the file, or you can export particular shape from Flash file using one tool (i.e. FFDec), modify the drawing file in drawing tool of your choice and then import the shape back using the first tool.
I can do export/import using FFDec. I use Inkscape (freeware) to modify vector graphic files (SVG format) but I'm not good at drawing.
The important thing is that we need to keep the drawing in vector graphic (means set of lines and fills) for Flash, not to convert that into bitmap graphic (pixels). So the drawing tool has to be vector graphic based. That rules out MS Paint. :-)
Attached example is Kristy body shape file exported from Flash. Please try to modify that.
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