We are putting together the first module for Sertorius and it's going to be a free PDF. Our original goal was to include a short adventure in the rulebook, but we ran out of word space. So it made sense to write a complete module called Beneath the Banshee Tree and release for free in PDF. That way, anyone who buys Sertorius can just download Beneath the Banshee Tree and start playing.
Currently, Beneath the Banshee Tree is being playtested (anyone who wants to participate can contact me at BedrockBrendan@gmail.com) and reviewed. It's a mystery adventure set in Talyr, a mountain city ruled by a troll who the locals worship. The module provides an overview of Talyr, several NPCs, a guide to introducing mysteries and managing clues, and a villain who evolves and grows over the course of the adventure. And once again, it will be completely free to download.