Currently, all IMPLEMENT_SHADER_TYPE macros need to be defined before the shader system is initialised. This means that any plugins that have shaders need to be preloaded specially, and this requires editing the source of the core module.
To make plugins more self contained, there needs to be a way to work around this requirement. The cheap and nasty way would be to have a list of plugins that have shaders listed in an ini file somewhere.
Cheers