Thank you for your answer
It worked well, but $mymoddir var didn't.
It returns an empty string (the link returned is:
http://space/index.php?id=1 where space is my localhost).
I had to edit templates/blocks/tinycontent_content_block.html like this:
<{$content}>
<a href="<{$xoops_url}>/modules/tinycontent3/index.php?id=<{$storyid}>">more...</a>