SAS EuroBonus - Booking LH flights on the SAS web?

Hi, I am booking ARN - NCE.
Going to the staralliance.com flight search I find a flight ARN-FRA-NCE that fits my schedule and half the cost of ARN-CPH-NCE. First leg is SK operated. It links to flysas.com for booking. However at flysas.com I have to choose a country and when moving forward via the swedish pages, I am only presented with the ARN-CPH-NCE option.

Is there a way to book the LH routes within the "SAS web"?

If I book on lufthansa.com, will I then be able to choose seats, use fast track at ARN etc?

Thanks

It is not possible on the SAS homepages.
But do go ahead and book on lufthansa.com, SAS is handling CI at ARN anyhows, so you will be able to do OLCI on the SAS site.

or use wideroe.no

Thanks, can I choose seats at reservation on Wideroe or Lufthansa.com
I really need an aisle seat....