Re: FTP isntall - directory permissions
You can change the db/ folder back I think although you may need to tweak some files.
templates_c will always need to be 777 in your case, along with the cache folders, as apache needs write access to these areas.
If you hop over to http://mods.tikiwiki.org and click the Guides link, there is a useful guide called How to Secure your TIki which may be of use, it also covers removing files after installation that arent needed to sit on the host too
Hope it helps
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