I just verified a really nasty bug where nuggets stop clearing new construction areas, delivering resources to the construction sites, and not constructing

If a new couple can't get into a new house, they also will not breed

A save/load does fix this, but only temporarily.

If you notice things not being built:

1. Make sure at least 15% of your total population is labor
2. Make sure Raw food and cooked food is twice the population
3. Save the game, and load the game and see if the problem goes away
4. If you have done all of the above, and the issue keeps coming back, click priority on every building being built