Hi Carin,
Thank you for editing your post. As this is a community forum, where users of SEBLOD help eachother, we ask that you maintain a level of politeness with your posts by saying a greeting at the start, and thanks at the end.
The seb_map template does not include clustering. This is not listed as a feature on the products page, nor is it exemplified on the demo website for this product. You will need to modify the template yourself to add this in if you need it, or find someone who is willing to do it for you.
Cheers,
_jrmo