Replaced control board and now clock flashes and oven still don't work

That is a very simple and all inclusive control. The power comes in and the oven control then applies power and interprets the input from the oven sensor as needed. There is nothing else that would cause the issue you are having other than a faulty control. You may want to confirm the neutral and ground are good to the range, but I do not suspect you will find any issues with it. The control will need to be replaced and should be under warranty.