"Most used" list (in Start Menu) is problematic

1) I use Word much more often than others in the list. Why is it not displaying?

2) Can I add to the number of apps which are displayed?

1) You can try resetting the "Most used" apps by turning them off and on (Go to Settings -> Personalisation -> Start); when you next use Word it should appear there.

2) Once you have expanded the size of the window the number of Most used apps increases to 6 but no more.

I had Word as a tile...Once I unpinned it from the tiles, it appeared in the "Most used' list.