Modern engines are manufactured to much more precise standards than back in the day when break in was very important because the rough finishing of the pistons/cylinder walls/rings meant that small metal shards had to wear off when it was first driven so everything would become smooth. Now the only important thing is to seat the piston rings and guys that have tried this both ways and torn down engines years later to look find that going a bit harder on your car is actually better. The things to take it easy on are the brakes and clutch. If its an auto, take it easy right off the line until you get up to speed a bit. Its usually good to go about 60-70% of throttle to about 75% of your redline and then let off the throttle completely and let the engine break until your revs drop to 2500-3000, and repeat over and over a few times. Letting the engine brake your car helps seat the rings. Seated rings prevent blow-by (exhaust gas forcing between the cylinder and cylinder wall). Obviously this is much easier on a manual car. If its auto I'm not too sure if you should put it in 2nd or 3rd (often 'drive') and do this a few times. I don't have any experience breaking in an automatic car.
Mostly though, just go really really easy on the clutch/brakes for as long as the manual says the break in period is. Also, no cruise control, keep varied speeds.
72Km is no huge deal, but I might make a stink and get some free oil changes or something. Scratches absolutely should be fixed.
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