You are missing most of the structural code that creates the sidebox content. Look at another sidebox tpl_ file like information and see what it has that yours doesn't, then adjust your tpl_ file accordingly. You may not need everything - compare several files to find the common elements.

The easiest way to make a new sidebox is to download the Blank Sidebox mod from Free Addons - it has all the proper parts ready for you to customize.