Sounds to complicated to me.
But I bet you will have it going.
There are 3 buttons. One sets the programme type and can be ignored (having set it to the loop programme, I have actually snipped the button inside the case, so it isn't an easy accidental press).
Pressing the second button puts you into configure mode, first for the first timer (how many seconds OFF), then for the second timer (how many seconds ON).
Pressing the third button changes the time setting.
So if I am in 180sec/60sec mode (Smoke) it takes less than a minute to change that to 60sec/60sec mode (Medium). 0sec/60sec is "High".
Pretty simple, especially when you consider you have a variety of settings in-between Smoke/Medium/High.