You may have problems when you create more labels (different colors for different file types and/or "modified within.." as in your case, plus some more). These filters will start override each other.
For "modified within.." you should tbone's script:
[url]Column: ModifiedWithin (alternative to 'modified'-labels)]
It works perfect. On the picture below you can see some filters "in action" (bold is for folders, colors for file types) - and one additional column (small square) indicating "modified within" files.
