If you want to use html in a var that is being passed to the template, then you must make sure that escaping is off for that particular tag, i.e.:
... in your php file
$htmltext = some textbr /on a new line;
$tmpl-setVar'myvar', $htmltext;
.. in your template
tmpl_var name=myvar escape=none
This will allow you to put html in your vars, otherwise, vlibTemplate encodes html in vars by default.
Have a look at the tmpl_var and options sections in the docs.
Regards,
Kelvin