The Z-stroke I was talking about defines your build volume height (see screenshot)
However, version 1.0.4 doesn't have that in there yet, but there's a few tricks you can use to do this. First, the slicer will only start slicing at the build table surface. So if you position your object 10mm below the build table (so that part of it is literally going through the table), the slicer will only start creating G-Code 10mm up the part. You can do this by double-clicking the part to bring up the custom positioning dialog.
You can also use some creative G92 commands to change the origin location for the print. So what I might do is manually zero my machine using the "Home All" button in the machine control panel. Then jog the Z-axis up by 10mm. Then press the "Zero Position" button that will send G92 X0 Y0 Z0. That tells the firmware that the current location is the origin (0, 0, 0). You could then print the G-Code you made in the step above by tricking the slicer to start slicing 10mm up.
We get that this isn't the easiest procedure which is why we're making some better tools to do this. Does it at least make sense how you could do this right now if you really wanted to? Also note that you would need to get rid of the G28 (home all axes) in your starting G-Code if you use this method since you are tricking the machine to thinking the home position has moved and a G28 would ruin that.
But it sounds like you're talking about something else. We are actually already working on some new features that will make this a breeze, such as defining what Z-heights you want to start and end printing at. We specifically came up with the idea to help with multi-color printing, so it sounds like that's what you're looking for.