hi, thanx for the response and for encouragements but could you tell me (sorry..really beginner) how to do for ground check, I mean: red wire of the multimeter on...? (number and letter to locate it .. do you have noticed the letters and the numbers on the image I sent in the first post)
For the resistor, I actually checked it before putting it on the board, but I was talking about the resistance of 5 kohm of the non connected pins as said in the tutorial :"The first test is called a connectivity test. Get out a multi-meter and do a connectivity test to make sure the pins that aren't supposed to be connected aren't connected. If by chance you accidentally bridged power and ground, your circuit could spark and your batteries melt. If you put the multi-meter on the resistance setting, make sure all non-connected pins have at least 5 kohm resistance or you may have power issues"
...and also how to check if non-supposed-to-be-connected-pins are or are not connected
..and for the regulator which should be 5V, am I right if I do like this: red wire of the multimeter on C5 and black wire on D9..?
I hope that my question is clear and thank you for future help