You can download the trial version of the software thru the page linked below without the download assistant being involved.
Be sure to follow the steps outlined in the Note: Very Important Instructions section on the download pages at this site and have cookies enabled in your browser or else the download will not work properly.
Photoshop/Premiere Elements 12: http://prodesigntools.com/photoshop-elements-12-direct-download-links-premiere.html