Maps are split into groups of 5 map size ranges.
As you can see from the menu above, these are 0-9, 10-19, 20-29, 30-39 and 40+.
This refers to the LONGEST screen size measurement.
For example if a map is 12 screens by 30 screens, it will be listed under the 30-39 maps.
Minimaps are displayed for each map, I currently have the following :-
Maps 0 - 9 = 2 (all uploaded)
Maps 10 - 19 = 51 (all uploaded)
Maps 20 - 29 = 63 (1 missing)
Maps 30 - 39 = 13 (all uploaded)
Maps 40 plus = 12 (all uploaded)
Own Maps = 6 (1/2 complete)