A similar thing happend with me when i flew NCL to DEL via Paris on Air France last summer. I got my luggage 3 days later and most of it was missing, including a very expensive bottle of champagne.

I tried and tried to get some compensation or even a acknowledegment that it had happend and nothing. They didnt even apologise.

I have been lucky with KLM in that this has never happend with them but me and a friend flew to Prague last March and upon arrival his suitcase was damaged. We went to the counter and the lady looked at the damage and asked how much the bag was worth and within 5 mins he was walking away with a voucher for £100 (which he ended up losing on the holiday)