Attached is a diff of changes required to make sbbs.el run on GNU Emacs version 24.5.1. The text-properties-search library is not included with this version, subrx is missing cxxxxr, and cxxxr functions, and tabulated-list-print does not have the UPDATE parameter. I wouldn't be suprised if I broke sbbs--insert-sxml-par since I've removed the narrowing not knowing what it was for but it seems to be working... Instead of searching for the 'action property it should also be possible to collect the indices of these properties when they are first parsed in sbbs--process-sxml and then iterate over these applying make-button on them. I've not done this so as to modify things as little as required: https://paste.textboard.org/2fce1e47
Also I'm getting Error while submitting: (http 500) which I don't know how to resolve, but haven't looked into yet.