It worked for me, out of the box. I use NetBeans 6.7.1 and this is what I did
- Downloaded the plugin .nbm file from the location you mentioned
- Install plugin as explained here
- In an existing project with web stuff, File-->New File-->Other-->Empty Smarty file
This generated at .tpl file with just
{*
Author:
Smarty template
*}
in it. As explained on the plugin download page, outside the Smarty tags you get only basic functionality in as well php as html segments of the file, but as far as I can see the syntax coloring of php and html is OK. Code completion works fine inside Smarty tags.
Regarding syntax analysis: I created a number of errors is html and php in the tpl file and it seems to pick them up correctly.
So, while it's annoying that you loose code completion in html and php it looks quite usable and useful to me.
Let me know if these instructions solved your problem.