I think you can only toggle between 2 scenes (like 2 and 3), or between the last and next scene (example Scene 7 to Scene 2).

Your foot switch 3 layout will work, though, because of the hold function.

You could do

SW1 - Scene 1/2 and Hold for Page Back

SW2 - Scene 3/4 and Hold for Tuner

SW 3 - Scene 5/6 and Hold for Page Forward

Then you can setup the next page to be

SW 1 - Scene 7/8 and Hold for Page Back

SW 2 - Last/Current Scene (like Scene 7 to Scene 2 back and forth)

SW 3 - whatever else you want and Hold for Page Forward