One more question and then i start preparing to format/change.
What happens if i don't manage to get bitcoin client back online when auto payment happens?
Is it in "bounce" and i receive it when client is online? Or is it lost cause?
You can be online or offline, it's almost the same.
If you are online, you will see the payment instantly and when it's included in some block it will be confirmed.
If you are offline, you will usually see the payment when it's confirmed.