Hi,
Unable to add a language, is it not possible to add ?
Thank you

Yes, in footer .php
find:
<?php if(osc_get_preference('site_info', 'veronika_theme') <> '') { ?>
        <div class="info">
          <?php echo osc_get_preference('site_info', 'veronika_theme'); ?>
        </div>
      <?php } ?>

replace with:
<div class="info">
  <?php _e('Free classified...blabla', 'veronika'); ?>
  </div>
open your translation *.mo file and ad in the bottom line
#: footer.php:79
msgid "Free classified...blabla"
msgstr "Your translation...blabla"
compile to PO and upload to language folder, as usual, there are many discussion on forum how to translate if you have a doubt.