It cannot mean that they should all be present as in the previous Pasuk, since once Yisrael enter Eretz Yisrael, that is not feasible. Refer to 24:15:3:1 and note.
3)
Why does the Torah insert "ka'Ger ka'Ezrach" here?
1.
Seforno: To dissuade us from thinking that the Mekalel was punished because he was a Ger, since a native is equally guilty for blaspheming Hashem.
2.
Sifra: To teach us that the distinction between one who curses with the Name of Havayah and one who curses with one of the other Names of Hashem
1
is confined to a native and a Ger, but a Nochri is Chayav Misah at the hands of Beis-Din either way.
2
Though it is not clear as to why this is necesary, seeing as we already know that women receive the same punishment as men. See Torah Temimah, in Acharei-Mos, 16:29, note 30.
5)
Why does the Torah repeat the words "be'Nokvo Sheim"?
1.
Sanhedrin, 56a: To teach us that one is only Chayav Misas Beis-Din if one curses the Name of Hashem by the Name of Hashem.
1
2.
Sanhedrin, 66a: It teaches us ('Im Eino Inyan')
2
that one one is only Chayav Misah for cursing one's parents if one curses them with the Name Havayah,
3
