how can i rotate buildings when i place them
There is a Mission Builders Forum for that kind of question m8. Suggest you delete this thread and start a new one there.
Kill the Wabbit, Kill the Wabbit, Kill
Zoom in on the map till you see ground detail.
Press "Enter" on keyboard (alpha)and use numpad keys
Joint-Ops Virtual Combat Schools
I've got a tutorial on that and other basics of the FMB, here: