Well, that's a major mistake. You can download a version of bclut2.aco from the ftp site that will work on Macs. Though the browser-safe clut is something we recommend you use on your pages, the one at the FTP site isn't our favorite. If you're having trouble reading the .aco file directory, go to the New Rider's Update Page and download a fix. It's not the Coloring Web Graphic's CD, it's older CD drivers that don't recognize directories that begin with .
Unexpected problems occur when working with browser safe color.
Sometimes browser safe colors that you thought you set up properly turn out to not be browser safe when you checked on them later. One of the main reasons might have something to do with your computer's current bit depth. For some unknown reason, browser safe colors aren't represented by thousands of colors systems. The only solution to this problem is to work in 256 colors or millions while selecting and saving with browser safe color. The moral of this warning is, make sure your authoring system is set to 256 or millions of colors when creating browser-safe artwork.