Hi krileon:
I think CB doesn't have trouble finding his way. The only thing I must to do is to apply public access to the menu item I already have, instead of for registered users only. I have done so and then all works as expected. My goal was not to allow public access to user profiles. Since the profile menu is a item of a registered user's menu, which only registered users can access to, the goal is done, so this part can be considered resolved.
To the message styling, please need to tell me in which file I have to edit to add the HTML code
Thanks