You still have something wrong with your testing server url setting and/or local folder path... or your local server doesn't have the MySQL or MySQLi module installed as the error states.
Create a new file in dreamweaver... call it "test.php" and just put this in the body "Hello World"
Then save that file and go to your site settings for your testing server. Copy the url you have set and paste it into the browser and add "/test.php" to the end of it. Do you see the "Hello World" page?