Did you check the timing with a light?

You should never let a new engine idle prior to break in.
Vary the engine rpm: 1500, 1800, 2000, 2500, 2000, 1800, 1500, 1800, ...
holding each rpm 5-10 min.

You should have no parts damage if it was only hot a couple of minutes.

I always fill the systems through the block vs through the radiator.

If it boiled over that fast, I would have to suspect a head gasket problem. Do a cooling system pressure check. Your local Big-box parts store will loan you a tester.