did you make sure that the fire will keep bruning when you leave the game i once forget and over night 5 villiagers died, less food now warm wasnt good.
also try to let your children collect much muschrooms especially the red ones (they gave more food points then the brown) and set game on 1/2 speed before shout down for longer. so make sure you have enogh food and fire and some who still collecting foods.
at the beginning dont care a lot about the puzzels. try to get tech points for farming an budling so you can build the damm and farm the field.