How to manage page results layout

I’d like to know how to manage these things in layout

(1)
here
http://www.sinaxi.com/apps/b/test-ricerca/?geodir_search=1&stype=gd_place&sarea%5B%5D=&spost_category%5B%5D=&s=+&snear=&sgeo_lat=&sgeo_lon=
When in sarch bar I leave AREA field without select nothing inside (not specified AREA items) I want to see ALL items (cause of no select in Area select field…. so means to consider all items)

(2)
How can I set default view for search results as Grid2 for all users ….and don’t allow user to change this.

(3)
When I open main page
http://www.sinaxi.com/apps/b/test-ricerca
is OK to show all items in map (great)… I’d like to see also also as items result.

(4)
How Can I increment items to show for every page

(5)
I’ve seen that there are PINS that are group of mains pins… when I click over you “explode” PIN showing others included.
In other maps I’ve seen a different approach with a circle with number of PINS included. Is it possible to do the same?
Is more clear than show a PIN and know ONLY when I click over that is a group of other PINS.