Hi Tom,
I've been using Corona since the alpha versions and now happily pay for Corona's subscription. I use your render engine almost daily. I love it. As a C4D artist/hobbyist I was excited to upgrade to the more affordable R21 and I'm now paying for that as well. I've been refreshing these forums for the last few days in hopes of an update and frankly, you guys are being very dodgy and vague about this right now.
I'm a developer by trade so I totally get where you guys are coming from in not wanting to make any promises. I can only speak for myself but I think just a little more transparency would put my mind at ease. Right now I can only either use R21 w/out Corona or R20 with Corona, and at this point it feels like I'm just wasting my money since I can't use both on a project.
Are there any additional insights your team can provide for us plebs? Is there some sort of incompatibility issue your team is facing? From the outside looking in it appears as if the team is focusing on new features for R20 and not putting a lot of priority on R21 (I'm sure this isn't the case).
With the release of R21 being so affordable I expect a lot of enthusiasts like myself are going to be getting into C4D and Corona is a really easy to learn and accessible render engine that helped me a ton when I was first learning.
Thanks for all that you guys do!
edit: I missed one of your posts from earlier today regarding to porting version 4 vs. moving forward with 5, hoping for some good news!