From the screen shot it's not possible to tell where you've set the z origin.

If your material is 0.73" thick and you're setting the z zero in SB3 to the same as you're set the z origin in PartWorks then it should be cutting fine.

The cut depth and the number of passes looks like you've got a 0.25" pass depth on the tool which is fine.

I'm a bit confused as to why you think the bit should have been half an inch off the material because you underspecified it. If the material is 1.25" thick (for example) and you've set a 0.73" cut and you've zeroed the z on top of the material (with the origin set to match) then the bit should still have started on top of the material not half an inch above it.

You can zip the CRV file and attach it that way or just rename it to an allowed extension (such as pdf).