Dixen,

Aging depends on the speed setting of your game. If the mothers nurse for 120 minutes, then I think you're on 2X - and 60 minutes is one year (VV skips the 9 months part!).

Minimum breeding age is 18 - and there's no maximum.

The skill checks mark the villagers preference for work - however, if they don't feel like working, it doesn't matter what is checked. Have a look at your builders likes and dislikes - some of them just don't like working at all. Other than that, you just have to keep babysitting him - or give him another job and get someone else to build.

The skill increases are smaller as they get more experienced. They're usually fairly quick to get to Adept, but then can take forever to become a Master.

Zoelim, you'll know when the GC is born - but you need a combination of Level 3 techs to make it happen.