Some questions from a relative newbie

Anyway, some questions, if i may be so bold.
1. Whats that small yellow dot in the top right hand of the screen? whats does it do? whats it for?
2. Why when you hit lvl15 of upgrading to resources does it cost coins!! I dont mind if they were like 1 or 2 coins but 10 coins per upgrade!!! thats 40coins to upgrade a full mine!! I appreciate money has to be made but seriously, can this not be lowered a bit?.....or is it just me??
3. Negative crop output. My crop mines are at lvl15, planting tech is lvl7, and im struggling to get out of negative without resorting to oasis's. How do you guys have such massive armies?!?!? how do you cope? i have roughly 3k inf and about 700cats....and im struggling.....

4. When i attack another player, i scout, see he has lots of resources (goody!) attack, keep scouting, i win, but i sometimes up with 0 resources in all but crops which i get, how come??
5. Do forts have defences? I have farmed the odd fort (lvl2) and some had turrets? is this normal?
6. Scout. Scout is lvl5, some people i scout get full info, and some just a list of army, saying several or alot or stuff like that, how come some i see full info and some i dont.
Appreciate any help guys, thanks!
