1)
To whom is "Vaya'as" (which recurs throughout the chapter) referring?
1.
Ramban (on Pasuk 8) #1 (citing the Ibn Ezra): It refers to Betzalel, who personally made all the holy vessels.
1
2.
Ramban (on Pasuk 8) #2: It refers to each of the wise-hearted men mentioned in Pasuk 8.
1
See Ramban's objection to this explanation DH 've'Al Da'as R. Avraham'.y