It's been a long time since I logged in in this forum, and it's sad because it was awesome to participate and collaborate with the Corona team.
We migrated from max to Blender several years ago and we never looked back, we are happier with Blender than what we was with Max, but it seems there is no interest in the whole ChaosGroup family into doing a serious development of their engines for Blender, so I leave this message here so others that come with hope have things crystal clear, unless someone from the official team says the contrary.
Corona Render will NOT be integrated into Blender, there is no interest on it, saying that they will collaborate with someone that wants to do an integration for free is not serious, so in my opinion, with all due respect, ChaosGroup and Render Legion don't take Blender users as serious users, it's a pity.
I hope the team can change their mind, I know many people that wants to make the shift to Blender, but they would also like to maintain Corona as render engine, they will shift sooner than later because they don't want to maintain adesk licenses, but it would be pity for them to have to change their render engine.
We use Cycles and LuxCore, but we would also love to be able to use Corona for serious work.
A pity.
P.S.: the fear to GPL is not a serious reason, there is enough legal power behind Chaos to ensure that there won't be a single problem with that, and both Octane and Redshift did the integration and so far... not a single problem with the GPL, BTW RedShift is add-on based, not custom build based, there is no need for a custom build, there are many many solutions.