Well firstly to answer your question, i believe you need to alter this line and add target="_blank" within the anchor tag ( )
[PHP]">" alt="<?php echo translate("download");?>" title="<?php echo translate("download");?>" width="7" height="16" style="vertical-align:middle;"/>[/PHP]
i cant guarantee thats right as i only scanned the HUGE file you posted.
My second point is to menetion that you should try to post only the code rather than the large header of comments within the file. Posting the entire commends, change history and credits is just soooo long and frankly daunting to anyone who might want to help you :)
for example, dump the junk above:
****************************************************************************
** DESCRIPTION FILE FORMAT **
****************************************************************************