New builds can be found
here. I haven't had much time lately to work on the project as I've been busy with classes and work. Build 102 will work with plugins, and the development kit to make a plugin is there.
@programmers: Just remember if you do decide to develop a plugin it is likely that the dev kit will change slightly because this isn't an official beta release. (I think by this point the only thing I would be adding is functions you can call housed in the host class inside Spiritual which means you probably won't have to change your plugin code if I decide to change a few things - no guarantees though).