Cannot apply different skies on Iray Worlds SkyDome

DawnStar

I've read all the forum entries about this product and I see that skydomes can be a bit awkward! I select a preset scene and get a Base with Sun and SkyDome parented to it, but when I select Skydome and try to apply a different Sky shader to it nothing happens. I get the flashing notice - "Reading asset loaded file...etc, but nothing changes. 

I've gone into Environment and tried Draw Dome On and Draw Dome Off, but there's no change. Anyway, I gather that this product creates a dome within the dome and so Draw Dome On shouldn't make any difference in any event - although I hjave seen conflicting comments about this so I'm not sure. 

I did notice from a screenshot on another old forum entry that when SkyDome is selected, under Parameters there is Skydome/Morphs/Skydome/IR Skies - well I have that but without the IR Skies - it's just not there. 

My machine is powerful enough that I can work within thye quick Nvidia Iray, so it's not that I'm not using Iray - and anyway, even in a full render no matter what I do it doesn't change the sky. 

Any thoughts anyone?