I'm having a problem with this. I am in the Pocket Plane and I go into that challenge. It is in the desert-like setting, because I am evil. I walk in and nothing happens. I go out, rest, come back. Nothing. I close my game, restart computer. Go back in. Nothing. Has this happened to anyone else?

These are the mods I have installed, if it makes any difference.
Ascension Redemption Solaufein Valen Harder Last Battle ToB (harder Gromnir, Yaga-Shura, etc.) can't remember name. Thing that makes paper dolls like BG1

Maybe you said something wrong to the Solar, or maybe you've already done the challenge. If you have shadowKeeper, perhaps you deleted the Global thing that sets the cutscene thing up. I dunno, otherwise. Sorry I couldn't really help.

I practically skipped everything the Solar said, so that's possible, but I don't think I delated any global thingies. I'm pretty sure I didn't do it yet.