I finally found out what the transparency in the sky is for - it's so you can see the stars! :rotfl:
By playing with the sky colours I've managed to get the mod so that it is indistinguishable from normal GWX, except for this one thing - and I don't think it can be worked around
Well for me personally god's lightswitch is more annoying than no stars, so I'm happy, but methinks the majority of people will want their evenings starlit :hmm: