I just updated the script again. There's now a "Rainbow" button that you can click to turn off the edge color. Hope this helps.
If it does help please change your rating to a positive one :]
Later I might turn those big buttons into sma…
EDIT: TO ANYONE READING THIS THREAD:
The script works great, the problems described here do not exist! Tisaku Anyue is having problem with someone elses code and erronously blames it on me. There is no colored background, it's Tisakus Stylish theme …
It doesn't seem like this script will ever be updated by the author.
But I have written my own script that you can use to export entire fanfics. And I'm keeping mine updated.