In the past CK's I haven't had this problem. After resetting settings, reinstalling, scoping out the .ini's, reinstalling Skyrim:SE w/ no mods... I still have this problem in the Creation Kit, the Render Window is solid black. No matter what cell I load (int or ext) has the same result. Even when I have no mod loaded, just the Skyrim.esm... Now, the CK is definitely loading something because when I double click the area in the Cell View then mouseover the Render Window I can see the mouse icon change depending on what it is (presumably) hovering over.
Any suggestions would be greatly appreciated!
I'm going to go ahead and facepalm myself in advance because it is probably something simple I've overlooked...