i downloaded yii user management extension, a very cool extension but my main problem is to display the registration form and log in form of this extension in my theme, if i click on login it bring the form in the default theme instead of the customized theme please help
if you are using the login widget provided by YUM, you will need to update the form view of that to match your theme as well (this means including widget/form views in the "theme" folder - themes/classic/views/user/user/login.php)
It sounds like you have not themed the module views for YUM. By default, I create a copy of the view provided by the module (YUM login.php) in the themes directory: