Every time I try to edit the style sheet for a theme and save it, it won't update the theme.
Make sure ./cache/themes/ folder is CHMOD to 777
What are the folders inside ./cache/themes/ CHMOD to? And the files inside those folders?
cache/themes/ CHMOD: 777
theme1 folder: 775
theme2 folder: 775
theme1's files: 644
theme2's files: 644
That's using theme3, you've only listed the CHMOD's for theme1 and theme2. Are you sure you're editing the right theme?
I don't have a theme3 folder.
PM me admin and FTP login details if you want me to take a look.