Keep license as is. Conduct a study...
Could offer a unique customized (pro-longed demo) CIE version as is the case with Corona 1.6 Standalone for Blender.
I would even opt out for a single payment (<20€) or in the case of a 'study' - gladly allow the use of gathered data & provide my feedback - without any updates, fixes, customer service... purely, single product experience w/o strings attached.
Get some extra cash for the icecream and charry on top.
Would make a lot of clients, designers, artists and common users (all those not using Corona) happy ;)
And after a while you would see, if it's worth developing the CIE (post fx - compositing - tone mapping tool) into Corona Standalone Studio (using your proprietarry format - later on, possibly adding ABC, FBX, OBJ, STL importers).
There's a lot of inquiry for "Virtual photo studio" around CG forums - since for now, only options are: Maxwell & Arion (both old and slow, while almost all other engines need dedicated plugins/exporters/DCC apps) and are in technical sense far away from virtual photographic workflow.
... a thought long lingering...