When you say it isn't running in SV, what do you mean? It doesn't appear in the menus, it appears in the menus but no data is generated and displayed, or it fails in some other way (e.g. crashes)?
You might find it simpler to test in vamp-simple-host, which prints out its results directly to the command prompt -- at least that way you would see immediately whether there are any results or not, whereas in SV you could theoretically have results that simply aren't visible because their timestamps are wrong, or some such.
I can't really comment on the usage of aubio, but I would wonder what m_currentOnset is as it doesn't appear to be set anywhere.
To remove the example plugins, it should only be necessary to remove the references to them from plugins.cpp (or whatever file your library main entry point is defined in -- it's plugins.cpp in the example set). There are three references to each plugin (the #include for its header, the static adapter declaration, and the return value from vampGetPluginDescriptor), and you would need to remove them all. Ensure that your vampGetPluginDescriptor function returns your own plugin's adapter when it is called with index value of 0, and returns 0 for any other index value.