Hi,
yep, that's the technic I would recommand too. The other technic ( as in the Parse PlayMaker port I did) is to cache everything using a string reference, so withint PlayMaker all your objects are just referenced by string with appropriate set of custom actions toi go with it).
other then that, using FsmObjevt is a bit of work up front, but this, coupled with DFUI, I am currently achieving a very advanced MVC architecture with PlayMaker and it works very well indeed, DfGUI doesn't necessarly need to be used as the ui, I just use the property and event binding behaviors it features, incredible stuff and amayzing potential, even with playmaker.
Stay tune, because I have created a additional set of custom actions for DFGUI that address few missing features, and then you'll be able to see how I use FsmObjevt in very advanced situations ( binging at runtime, prefabs acting as MVC views, PlayMaker as the component, etc etc)
Bye,
Jean