This is the exact behavior I have experienced and posted about here.. http://communities.vmware.com/thread/446483?start=30&tstart=0
If I understand VMware correctly the K1 and K2 cards are not fully supported with vDGA yet, which I believe contributes to this "screen blanking" behavior.
As far as dual monitor support with the GRID boards, Linjo is correct, nVidia has not released a new firmware yet to enable this. They do have a beta firmware that supports this, but as of yet I have not been able to test with it yet. I would contact your nVidia rep and request the beta firmware.
