There is no reason to not simply do like Poltroon suggested. As a matter of fact, that is the method with the least risk to the eggs and/or much simpler than syringes. There is evidence that "rest periods" can actually increase hatch percentages, I think it's even mentioned right in the handbook. Keep in mind that mother hens hop off the eggs for a few minutes every now and again to eat and drink. Just pop the top off, pull out the egg tray (carefully) fill the reservoir as needed, and put the tray and top back on, simple as that. Getting water on the eggs isn't a good thing, why risk it, when simply doing the above is actually good for the hatch?
As for the lockdown period, filling both reservoirs as instructed just before lockdown should provide more than enough water to last the few days. That being said, I would like the auto humidity module, but it just seemed pretty pricey for something that isn't difficult to accomplish manually. I might still want it one day though . . . because I'm pretty danged lazy by nature, heheh, and I just like "automatic" stuff.