It was interesting to read your comments about your trip and I'm sorry to hear you had an unpleasant experience with SAS.
However, I do react when you nominate SAS "the worst airline" after one bad experience, that's really unfair.
The same thing could have happened on basically any airline and I guess many people could mention a handful of airlines which provide the same or worse service in normal conditions.
As a frequent flyer of SAS I've travelled a lot on SAS and experienced most situations, but not even once have I had any real problems.
Like most other people here I must say it doesn't really sound like SAS.
If you feel you're been treated very incorrectly I think you should write a letter to SAS and ask for an explanation, I'm pretty sure there were circumstances that different people along your trip could not do anything about.

Regarding SAS in CDG, they actually have their own staff there. I visited the airport two weeks ago and had a chat with the woman working in the lounge, I was the only one in the lounge when I entered and it turned out the woman in charge was Swedish.
SAS takes care of the check-in, the lounge and the boarding procedures themselves at CDG and most employees rotate between these three stations.
About 50% of the employees are Scandinavian, the rest are French.
I have travelled out of CDG on SAS several times and most SAS agents are nice and helpful. Having their own staff certainly improve the service a bit, CDG airport staff are not really known to be the most helpful.

When it comes to CPH, the staff there are normally very friendly and certainly not indifferent towards their customers. I have travelled to, from and via CPH lots of times and have only positive things to say.
If other flights were running late they probably had a lot to do and were very stressed and didn't provide the normal excellent service for that reason. Regarding not flying directly CPH-BGO, there are only about five flights a day on that route while you could probably find 20 connections if changing in OSL. There is on average one flight an hour CPH-OSL, the same on OSL-BGO. So it could well be that the next nonstop flight was fully booked or that you would arrive earlier travelling via OSL.