I just installed latest KDE4.2.1 Live CD x86-64 which downloaded from kde.org. After patch update,I try to add Packman repo,but this dialog appear :‘Unable to download list of repositories or no repositories is define’.
What problem is that? 
As you do not tell us what the exact URL is you try to add we can not tell if, and when yes what, you did wrong or not.
In any case it seems that YaST or zypper (again no mentioning of what you exactly did) thinks you made an error.
Probably due to the problem discussed in the News section. May not be working till some time tomorrow, but you can add it by hand. Get the URL from here: Additional YaST Package Repositories - openSUSE
Start software-installer, choose Repositories, remove the Packman entry, choos Add, choose Community Repositories, check Packman, OK, import the key, OK, OK, back to the software-installer and you’re done. It might even suggest to change Xine libraries, to make you able to use all codecs, such as MP3