Just to confirm, the issue is that when you are connected through Dreamweaver, if you also open a connection to the server with PuTTY SSH, you are disconnected from Dreamweaver?

If that is the case, I suspect that the issue is that your SSH server is configured to only allow one concurrent connection per authenticated user. As soon as you authenticate using another client, the prior connection is terminated. Depending on your SSH server, and the applications you are working on, the best solution would probably be to simply obtain a second login for PuTTY.

__________________
The best way to learn anything, is to question everything.