Not every plugin will convert over to be single player compatible; or rather it they would if we were not upgrading stuff as we go. The base plugin is a good example of a thing that will need to be rewritten from the ground up to make use of the new SQL tables rather than a series of interconnected INI files.
Generally the litmus test of whether something will be SP compatible is if it will make use of persistent data. If it does, it wont be SP compatible.
