Im getting quite a few of these type of entries in my logs: 

file not found   public_html/ow_userfiles/themes/macabre52b67c852a96d.css

and they are all from google bot.   So im wondering if it would do any hard to put a robots.txt file in the ow_userfiles/themes directory with a disallow to let the bots know not to worry about this directory. 

User-agent: *Disallow: 

Would that have any negative effect on the script to keep bots out of these kinds of directories?