vodka steeped in black currants--actually it was vodka flavored with black currant buds
Disappearance of Margarita, the Master, Natasha? We know from the end of Chapter 30 that the Master died in the clinic, and Ivan presumes that Margarita too has died at home.
Institute of History and Philosophy - While there was no institute with exactly this name, there were similar combinations, for example, LIFLI: the Leningrad Institute of Philosophy, Literature, and History. It was only logical that history and philosophy should be connected in a state where history had to be understood through the prism of Marxist-Leninist philosophy.
walks off with her companion toward the moon --Notice that when we last see the Master and Margarita, they are headed to the moon (like Pilate and Banga), not to peace.
Ivan is calm [peaceful] his pricked memory quiets down -- the wording is almost the same as that used in the previous chapter about the Master's memory. Ivan's peace, like the Master's, comes at the price of a loss of memory.
fifth procurator of Judea, the knight Pontius Pilate--these seem
in the English translation to be the words the Master says would end his
novel. In Russian, however, there is a slight discrepancy (again): Bulgakov
calls Pilate by the more customary adjective "Pontiiskii" rather
than the more unusual "Pontii" he uses elsewhere.