Arc Hydro on Windows 8 (ArcMap 10.1)

Hi,

I'm running ArcMap 10.1 on my Windows 8 laptop and it works just fine. But when I try to install Arc Hydro 2, the installer tells me it can't find ArcMap 10.1. I'm not sure if this is a Windows 8 issue or not, but has anyone installed Arc Hydro 2 on a Windows 8 machine?

Thanks,
-Ross