game http://www.littlegolem.net/jsp/game/game.jsp?gid=100369

Is it ALLOUD to move my player next to the goalkeeper in front of the goal and score? Or is it a bug

I tried. And here at liitlegolem I can Score

i think it is allowed, at least at here it is possible.

It's allowed. (Otherwise Tonywu can hold it on 1-1 forever.)

If it wasn't the decisif goal in extra time, then your player would shift automatically towards the midline to the first free space. (So in this case it would jump over the defender in the penalty area.) (In the boardgame the rules tell to shift the player towards the sideline in this case.)

But can I reach the ball from this position? May i walk behind the goal?

Only if you find a hole in the goal-net.

But you can reach the ball without walking outside the field.