As far as I know, all you can find as an
SDK tutorial is found in the SDK folder in BSplayer installation directory. By default:
C:\Program Files\Webteh\BSplayer(Pro)\sdk\
There you can find definitions for the BSplayer actions and call to be used in your C and/or Delphi projects. You can simply port these definitions to other languages (as I did in
VB some years ago :P)
Additionally, in the plugins subfolder (
C:\Program Files\Webteh\BSplayer(Pro)\sdk\plugins) you can find a couple of examples in both C and Delphi languages with the events definitions etc to create your own olugins (load, unload, etc.)
These files and a bit of knowledge in programming and you'll be able to create your plugins in a matter of minutes/hours.
If you create some cool stuff don't hesitate to share it with us