The non-rotating Cold Leg problem is a "feature" courtesy of vanilla Factorio 0.11.22.
![Smile :)](./images/smilies/icon_e_smile.gif)
![Sad :(](./images/smilies/icon_e_sad.gif)
Regarding your power production issue, check that you have
1/Enough pressurized-water in the reactor, reactor circ pump, hot leg.
2/Water in cold-leg
3/Water in cooling tower water source.
It would help to show me your setup with pictures. I can not help you blind.