Here is my understanding:
Desktop Coral works by "docking" to the side of the screen and claiming some space there. This tells the desktop not to maximize any windows over this area and keeps it from from other windows. Some programs can draw images into this area but you cannot drag and use icons in this area.
It's possible that there is a way to circumvent this restriction but I don't know of any.
And i'm afraid there is no way to make a full screen app show inside the reserved space; the only way to do that would be to install and run them on a virtual machine -- which would let you run them in a window, albeit with greatly diminished speed.
What you could do however is give up the dream of using desktop icons, and instead of Desktop Coral use a dock that lets you configure your own icons and buttons on it. Something like Launchbar Commander
. This serves the same function of reserving desktop space, but also provides a place where icons/buttons can be placed.
Thinking about the issue -- it would be possible to make a launch bar application that mostly simulated the look and feel of desktop shortcut icons. That is, it would let you arbitrarily place shortcut icons on it and drag them around as if you were working with desktop icons -- but in fact they would be items on the dock. But that's a lot of work to achieve something that i believe is almost entirely less desirable that a proper launchbar system of orderly icon arrangement.
My recommendation for people who want to be able to put their desktop icons in the reserved area remains: turn off desktop icons completely and use a launch bar tool.