This isn't a bug per se, but I ran into some errors with the exact location of the package directory. I cloned the repo today and followed the installation instructions in a conda environment (within PyCharm), then tried to create a SAM2ImagePredictor as in one of the examples. First, I got errors that hydra wasn't initialized. The init.py file wasn't even getting executed. When I initialized hydra manually, I then got the 'MissingConfigException' error.

I ended up having to copy the nested sam2 directory (sam2/sam2) into the site_packages directly so that it could actually find the package properly. I haven't worked directly with Python packages for a while, so maybe this is a well-known thing, but it might be worth a mentioning in INSTALL.md as a possible issue.