If you are asking can you make scriptworx install phpBB *.17 instead of *.16 the answer is maybe. You might be able to drop the new phpbb.tar.gz into the /home/interworx/lib/scriptworx directory and have it just work. I am not 100% sure if this will work, and it’s not supported.
This method will definitely not work with the new version of scriptworx that is coming out. In future versions of scriptworx, we may be adding mechanisms to allow a user to add a script/modify versions of supported scripts, but that has yet to be hashed out.