You may be hitting the same UI problem I ran into when adjusting this. Just mouse clicking would only produce two positions as you describe.
Try this: hover mouse over the selector thingy and use the mouse SCROLL WHEEL up and down to change the setting.
If it is like mine you will have three positions available.
It looks like you have the dot in the right place. There are limitations on how many insert effects can be active at a time. Are the two shown the only ones? Are they stereo or mono, etc.?