So I tried with the resistor but with no luck.
Must be low qualiity batteries or something because it can't even run the servo alone.
This is what I have tried in my desperation:
(just servo, no other stuff)
9v battery to arduino, servo to 5v arduino pin, gnd pin, and pin7 for control (servo "buzzes" for a moment but nothing more).
9v battery to arduino, servo to 4 AAs, gnd to arduinos pin and pin 7 for control.
9v battery to arduino, servo to 4 AAs, servo GND to 4 AAs, pin 7 for control.
No luck at all..
The jumper is in the right place for ext power.
I will buy a 6 aa battery holder like you zitron and some nice batteries. Maybe that will work. Otherwise I'll just have to wait with this stuff till I've studied more..
Must get a multimeter...
Thanks guys, I really appreciate it
edit1:
The weirdest thing just happened. I plugged it into the computer but changed the jumper to external. Also plugged in the battery. And it works, with head and everything.
Then I unplugged the computer and it still ran! But when I unplugged the battery and then plugged in the battery again nothing happens. Tried the computer method again, works like a charm.
It's like I have to jump start it with the computer 
Any ideas?