Okay this is a two-part request, of issues that are partially related, and which admittedly might be fixed or somewhat sorted by the next Alpha build release.
The first is the ability to have the renderer autosave (either the cxr orimage file format) at pre-selected intervals or pass numbers (whichever option you choose to render by) for the renders that take really long time, and also to pre-empt any crashes or program freezes by ArchiCAD itself.
Since cxr files can be reloaded and the renders resumed, this would be an invaluable feature for those mornings you wake up and find that the computer crashed or froze when it had about 30 minutes let to go to complete the render and you've lost everything.
I believe Maxwell renderer had this feature and ability and it saved my bacon on more than a few occasions.
The second (which is the one I think might have been sorted), is the ability to save the final result as cxr from the ArchiCAD save as dialog when you render straight through the ArchiCAD render setting rather than Corona's VFB.
Currently the only way to render the image and keep the pre-selected image size and aspect ratio is through the ArchiCAD render dialog and not the VFB which either distorts the image for images that have ArchiCAD's 2-point perspective turned on or with which you have to stretch the window and "guess" the image size.
Naturally I would prefer to do the render straight from Corona's VFB since that gives me all the options and benefits of Corona with the interactive adjustmens of tone-mapping and whatnot and also saving out render elements as separate layers, Lightmix and most importantly saving as CXR which allows on to continue to edit the image in Corona's image editor.
But until the 2-point camera perspective issue and the image size issue is sorted, we have to render through ArchiCAD's dialog to keep the same image size, but that does't give you the option to save as CXR (Which I assume would them allow me to access the render element layers from Corona's image editor).
It's possible one or both of these issues have been sorted out already in which case disregard, but otherwise they would be greatly helpful - especially for a progressive renderer like Corona.
Oh, and one other thing:-
In 3ds Max it's possible to clone the VFB image into a 3ds Max image buffer and that's also useful in a lot of ways that people use the renders.
I'm not sure if this ability would be possible with Corona's VFB onto an ArchiCAD 'image tab' but that would also be useful particuarly if the VFB issues I mentioned above were fixed, but also in helping evaluate changes between different settings as we're working along.
This one might be more complicated I admit, but if there's any possibility it would be greatly useful