Usergroup Manager > Edit Administrators > Username HTML Markup
Quote:
Username HTML Markup
The first field is the opening tag. The second field is the closing tag. These tags will be inserted around the user's username like this:
[opening tag]username[closing tag]
Some HTML tags you might want to use here include:
Where isn't it working? Maybe they are also in another usergroup and you allow them to pick that usergroup for colors? Or, perhaps you need to describe a bit better where you want the username color changed and exactly what you put in each of the two boxes I mentioned above.