There are a lot of helpful articles and tutorials in the Getting Started section of the Dreamweaver Developer Center. To work successfully with Dreamweaver, you need a solid understanding of HTML and CSS. There are free tutorials for both at HTML Dog:
Also check out Get up to speed with CSS layouts.
This issue has been fixed in the 12.1 Creative Cloud update. A fix for perpetual licence holders is in the works. More details.
If you're having general installation problems, . There's also a dedicated sforum for Downloading, Installing, Setup. When posting there, give details of your system and any error messages you get.
Note: Some tutorials are on non-Adobe sites
The Dreamweaver Cookbook contains a collection of articles describing how to perform a range of tasks - some simple, others more advanced - in Dreamweaver. You can also post a request for someone to provide a recipe for a particular task.