1)
To whom does "u'Shemartem es Mishmeres ha'Kodesh ... " refer?
1.
Seforno: It refers to the Kohanim, who are obligated to guard the Mishkan within the planks.
2.
Sifri: It is a warning to Beis-Din 1 to warn the Kohanim to perform the Avodah properly, because when the Avodah is performed properly, it prevents punishments from coming upon the world.
1
See Torah Temimah, note 5.
2)
What are the mplications of the word "ve'Lo Yih'yeh Od Ketzef"?
1.
Rashi: It implies that there should not be anger again, like there was earlier - in 17:11. 1
1
Torah Temimah: Like the Torah wrote in No'ach, Bereishis, 9:11 "ve'Lo Yih'yeh Od Mabul".
