Calibration

[Slatye]

a. How do you envisage calibrating the system for the increase in Z-axis by each drop

There's probably an easier method, but the simplest way I can see to do it is to just drop a ruler in the container, let it drip until the water has risen 10cm or so (the bigger the better), and count how many drops that took. If you can get it accurate to 1mm (should be fairly easy) over a 10cm total rise, that's 1% height accuracy - which is probably fine for most things.

b. How much of the initial 1.1cm depth of the resin does the laser harden

That'll probably be somewhat adjustable. If you scan super-fast, you get a very thin layer. If you leave the laser pointed at one spot for two hours, you end up with a very thick layer.

c. Does the thickness of the hardened layer reduce as the resin is consumed?

Unlikely, unless the resin layer floating on the water is so thin that the printer can't actually reach its standard layer thickness. Obviously the solution to this is to start with more resin.

d. How do you compensate for the usage of the resin during printing?

As gillza has said, that probably won't actually be a problem. The solidified resin still occupies volume in the bath, just like the non-solidified resin did.

If it is an issue (indicating that the resin shrinks or expands when solidified) it should still be fairly straightforward to fix. The software knows how much resin has been solidified, and therefore knows what volume change has occurred. If it knows the surface area of the liquid in the print container, the true height deviation is trivial to calculate.