No backtest after optimization

A very common bug is the backtest to become inoperative after an optimization ends.

Notice that to keep only 20 best results to display is a very small number. Then, many times you need, after an optimization ends, to click on the APPLY buton to copy the cbot parameters of one optimization you want to see but is not among the first 20. And next you click on the backtest play button. What happens? Does the backtest run? No. The backtest does not run.
Usually, I need to close the chart instance and reopen a new one so the backtest returns to work. But then you lose the optimizations .... and you need to save what you need to see in several files before you close the chart instance!
Sometimes, to rebuild the cbot "solves" the bug.

Also, notice another similar bug... many times, if you try to optimize and click... it starts and after some seconds it stops. It only runs normally after you rebuild the cbot, even if you already had done it. You need to do it again, and again, and again... before you start an optimization.

Lavio