So i bought an external HD ..in hopes of getting sonar platinum on it before servers are gone(if they go)...so i will have it in future when i upgrade to a new computer...im hoping the community can help me do this and im sure many would want the info as well..any help or direction would be greatly appreciated.
Thanks
Mike

While I encourage everyone to back up the installers, the urgency is gone with the BandLab announcement. The installers are in your account and in the Download Cache if you use the Command Center. By default the Command Center stores the installers in  "C:\ProgramData\Cakewalk\Command Center\Downloads"
 
Copy the installer to the external HD for safe keeping.
 
Note: ProgramData is a hidden folder.

You may not need to do that if the servers keep running for a while. 
 
In any case, the activation for SONAR is machine specific, so just having the program files on an external drive would not let you install it on a new machine unless the servers are still active to provide the activation token for the new machine.

Since SONAR depends on the registry for a lot of data, installing the application on an external driver is not practical. The external drive better used as storage for the installers.