Well, could you exactly tell us what you mean by "does not work as expected", this would really help.

Also, I noted you said you build the project "as per example". But you also said that "led connected to pin 33 power on sometimes". BUT there is no led connected at pin 33 on the example?

You may have wrong capacitor size, wrong crystal or wrong config, that can explain the strange behavior of pin 13/14.

Exact schematic would help too.

J-P