Halacha Yomi(m) 76, 77-

1)One should struggle to have wax for Havdalah in order to make the Bracha (Moreh B'etzbah 5:163).

2)For the fourth Seudah, one should really use Hamotsi, but if it's not possible he may use Mezonot(Moreh B'etzbah 5:164).