Sorry this is so confusing, Rob.
My SubframeSelector branch,
https://github.com/cameronleger/PCL/tree/SubframeSelector, is based off the latest PCL commit and has all the SS code up-to-date. I merged the latest PCL at the end of this development cycle so that a Pull Request would be clean.
The tag for my release was automatically added when I did a 'release' in GitHub, but that appears to have automatically applied to the 'master' branch which is actually the plain PCL repository from a while back... It also appears that the automatic zip of the code has the same issue. I'll see about moving that tag to the correct location, and that's on me for not understanding what GitHub does automatically.
You are right that PCL sets an API version 161, that happened six months ago here:
https://github.com/cameronleger/PCL/commit/97e83fd6747bcf5655a4caf395a6109c348c79e9.
Comments indicate it applies for 1.8.5.1357, and yet I'm running 1.8.5.1352 also and had no issues with this build or loading the module. For some reason, the Linux 1352 doesn't care about the API version change while the OS X 1352 does.
For what you want to try, it should work. Since I haven't modified any files outside of the SubframeSelector folder, you can probably checkout any PCL commit you want, copy that folder in, and try building. I can't imagine that I'm using any extremely new portions of the PCL.
Aside from fixing the 'release' on my GitHub, let me know if you'd prefer I do anything else for you. While I cannot do the OS X build myself, I can do whatever magic in the structure/code/files that makes it easier for you.
EDIT: The tag is in the correct place now, and the source zips were automatically updated with that as well. Looks like the same issue applies to previous tags as well.