Rapture 1.2.1 Microhost in Win7 64 Problem

I've just installed Rapture 1.2.1 on my new Windows 7 64 bit system.  If I run the Microhost, Rapture does not recognize my MIDI input, even though the device is checked in the MIDI Menu.  No sound.  If I set up Rapture as a plug-in synth in Sonar 8.5.2 it works great, no problems.  I'd really like to be able to run Rapture outside of Sonar.  Any ideas what I need to do to get the Microhost application going?  (MIDI device is an Axiom USB keyboard.)