Hi,
please clarify me certain issue.

During executing a March order it's acceptable to start only one battle, Let's look at three cases:
1. Move units into area containg units of another house. Battle: yes. No more attacks: yes.
2. Move units into area containg neutral forces. Battle: no. No more attacks: yes.
3. Move units into area containg only power token of another house. Battle: ? No more attacks: ?

Please explain me what's happen in 3rd case. May I take over control of area containg power token and start battle in another area at executing the same March order?

You can occupy as many as you like. Garrisoned neutral cities and territories with enemy troops are the only ones that count as a battle when you are executing a march order.

You are not really attacking. You are taking over an area that is loyal to the other player, but that they have no forces to defend with.