WOW has DX and GL modes, a quick search revealed. Defaults to DX.
Thing is, I instructed the wow-less friend to download and install the same DX redistributable (Nov08) I downloaded to be able to run Construct.
Perhaps she didn't get it right. I shall investigate in person and report back.
Oh and people are fond of clicking big OK or NEXT buttons without reading. Have the OK button take you to the DX downloads page and you'll have most of them staring at a list of downloads like this O_O
not perfect, but closer