By the way, I found that with minimum modification "coronaProxy.gsm" object work pretty well with Grasshopper connection plugin. see image 1 for the GDL modification needed.
This workflow is a good poor alternative for scattering objects all over the place using Grasshopper for controlling scale, rotation, preview style or even source file for each scattered instance. Response time are pretty good between GH and ACH, Tried with 1000 tress.
Corona Developers could by default add the boolean parameter "ParamcontrolByGrasshopper" to their coronaProxy.gsm objects, in order to be used directly without the need of any GDL tweaking.