OK, the prototype's working now, except for a minor problem which is that it glows in the opposite compared to the chip's output. I.e. when the test LED is lit, the strip is not and vice-versa. So, you will notice this very much especially on the slow setting. Not only that, in the video its flickering but in reality, it does not flicker..... much.
Anyhow, tomorrow evening I will try to get it soldered into a stripboard if possible. And the power fed into it must be at 12 volts and no more.