redirect profile url's

hello,
To maintain 4000 older profile URLs, i have to change user profiles url's from DomainName/UserProfile/UserID-Username to DomainName/Username

i read this page :
www.joomlapolis.com/forum/145-community-builder/193186-short-profile-url-mysitecomusername
but did not find the solution.

what is the best way to do it ?
if CB Redirect Bot is the best way please show me how to Use REGEXP for "From" and "To".
as i already mention the "From" is DomainName/UserProfile/UserID-Username (for example atar2.com/Profiles/3844-jimi-hendrix)
and "To" is DomainName/Username (for example atar2.com/jimi-hendrix)

Thank you,
Uri

What you're wanting isn't allowed by Joomla. Joomla needs to know the destination component. That's what the menu alias helps solve. It determines what view of what component. Without that it has no idea where you're trying to go. So Joomla will see /USERNAME as a menu alias, fail to find a menu item, and result in a 404. So you could create a custom 404 error page that handles checking if it matches a user then redirect or you can add custom rewrite rules to htaccess.

i already have an old joomla1.5 + sh404sef with 4000 user profiles. profiles url's are domainname/username.
now i want to upgrade to latest joomla3x without sh404sef and to maintain older URLs.

i read here:
www.joomlapolis.com/addons/cb-redirect-bot
that CB Redirect Bot is "Great for newly migrated sites that want to maintain older URLs".
so i think it will help me.

i see many people need to change profile url's like i do. Can you Please write a detailed guide with exact instructions ?
I do not want to get 4000 not found errors (404) after upgrading.

thank you for writing "create a custom 404 error page that handles checking if it matches a user then redirect or you can add custom rewrite rules to htaccess." but i'm not a developer and I would greatly appreciate if you would further detail your answer.
Sorry for my bad English...

CB Redirect Bot can redirect 404 URLs, yes. It will not redirect URLs that successful reach a destination. CB Redirect Bot is an extension of Joomlas redirect component. Once CB Redirect Bot is installed simply edit it within Extensions > Plugins to begin adding redirects. I am not going to make the redirect rules for you so there's nothing further I can suggest beyond what to use.