Z-Axis, starting position and flat based objects

Hi all. Me again
After have a good read of http://3dprintboard.com/showthread.p...libration-idea I was left wondering how the starting position of the z axis is "worked out".

I'm assuming at this point, as the peachy doesn't have a set floor like other printers, that it will be a 'simple' case of building/adding support structure up over a given length that is estimated to cover the unknown position and then printing the object with the intent of removing the supports after.
By this I mean.. Lets assume the wire frame that's being used as the base is 1cm from the base of the build tank but we're not 100% sure of the level and we start the build when/where we think the water level is around this point (by eye, but still it's prone to error), simply due to it being place by a human. Is the plan to add support structure for a few mm just to cover this error. I hope that make sense.

My second question is regarding flat based object.
It seems one of the limitations of the peachy is that the over-hang can't be as flat to the base as with other 3D printers. What's your ideas on building something with such a flat base?
Side note - I understand there will be a need to add drain/filling holes to allow the fluid to move around the printed object as it 'grows'.

Looking at the prints they have done it does look like an extended support structure is used to make sure your print is free of the wire "anchor" that acts as the base. It was also mentioned at one point that the peachy might print it's own base by drawing a grid on the first level that touches the wall of the printing area but I don't think we've seen any pictures of that working.

With regards to having to include holes to allow for liquid flow this shouldn't really be much of an issue so long as your print does not create any voids that are either:
Too steep edged and large to flood with each drip
not connected to a single "inlet" somewhere in the print.

There was an update aaaages ago where they showed images of prints that they had made to fail by adjusting things like this. There seems to be distinctive patterns and hole shapes that are caused if the juice doesn't flow nicely over the previous layer.