- Skin message suite.
 - Skin the parameter custom interacts.
 - Return native OFX types from the various param functions, currently tend to return via reference args. 
 - integrate/differentiate on all the various param instances,
 - Come up with a set of exception classes that the plugin can throw that will be trapped by the main routine so it can return an appropriate error code.
 - Exception specs on all functions.
 - test test test!
 - examples examples examples!