Bug and lagging citizens

Today i had a bug that 1 citizen would move at all and just starved to death, but he wouldnt even die he just stand there on lowest health, and after i restarted the game he was death.
And later in the game i got lagg, citizens werent walking normally anymore, a bit lagging.
I can move freely around with WASD and that kind of stuff, everything opens normally (crafting workshops etc) But the citizens are walking laggy.
I have only 12 citizens in my town.
I tried to lower every graphic etc, but wouldnt work, sometimes it got even worse.

I have an GTX 750 with 8gb ram i5 (i believe)

Hope someone can help, fix this.

A post was merged into an existing topic: So my mason decided it was time to starve to death