I have a Mavericks host, and I am trying to run any version of OSX within a VM on that host while retaining multiple monitors. OSX 10.8, 10.9, and 10.10 guests failed to give me more than 1 monitor. I repeated these tests with a Yosemite host, with no luck either.
It seems to me this is a Fusion problem, not an OSX config problem.
2015-02-17T18:43:36.762-05:00| vcpu-2| I120: Guest: svga: SetMode: mode w,h=1920, 1200 bpp=32
2015-02-17T18:43:36.764-05:00| vcpu-2| I120: Guest: svga: SetMode: pitch=7680
2015-02-17T18:43:36.764-05:00| vcpu-2| I120: Guest: fb: setDisplayMode: Display ID=1, Depth ID=0
2015-02-17T18:43:36.764-05:00| vcpu-2| I120: Guest: fb: setDisplayMode: wxh=1920x1200, bpp=32, pitch=7680
2015-02-17T18:43:36.765-05:00| vcpu-2| I120: Guest: fb: setDisplayMode: (1) wxh=1920x1200, 32 7680
vmware.log:2015-02-17T18:23:19.502-05:00| mks| I120: Current display topology: 6 displays, bounding size (5760 x 2400), scale 1.
vmware.log:2015-02-17T18:23:19.517-05:00| vmx| I120: SVGA: Maximum display topology 9600x3200.
VMware Fusion Help > Understanding VMware Fusion > Navigating and Taking Action Using the VMware Fusion Interface > Using Multiple Displays
-> Use All Displays in Full Screen View:
"Use All Displays in Full Screen is not supported for Mac OS X guests."
Fusion does not support multiple displays in OS X guest.
Another discussion below for your reference.
Thanks for your response, zhus. That appears to be for Fusion 6. I didn't see any similar notice in the Fusion 7 documentation; did you?
VMware Fusion Help > Understanding VMware Fusion > Navigating and Taking Action Using the VMware Fusion Interface > Using Multiple Displays
-> Use All Displays in Full Screen View:
"Use All Displays in Full Screen is not supported for Mac OS X guests."