Hey, very nice video. I am surprised it only displays warriors in such a short distance. I need to check what's going on with sprites, as they should be displayed at larger distances. Are you playing on Windows, Macs or Linux?
As for mines, you can build them only in specific locations. You can see very tiny drops of gold and iron shining in some places, but you need to look carefully around where they are. I am planning to release an update in a week or two times, so some issues should get fixed.