Can I ask that you;
1) Clear your Template Cache directory (/templates/compile) by manually removing all the files within that directory. All except "index.html"
Dont worry, the files will automatically be rebuilt.
2) Check the permissions of that directory. IIRC, it should be 755.
In addition, it looks like the tests for being able to write to those tested directories are failing.
What does your "Control Panel » Permission Checks" page tell you?
After making the changes, attempt to do the same procedures you've listed in your post again. The errors you're getting are server specific.
smartyPrepare($data); is the code which preps the entire page, before handing off to the Smarty template engine.