What is the translation of "Vayis'aber Hashem bi"?
Rashi: 'Hashem was furious 1 with me'.
From the word 'Evrah'. Note the similarity between the word 'Evrah' and the English word 'fury' (bearing in mind that a 'Veis' and a 'Fey' are interchangeable.
What are the implications of the word "Lema'amchem"?
Rashi: Moshe meant that it was Yisrael who caused him to sin. 1
Seforno: Because Moshe wanted to very much to establish Yisrael in the land permanently, that they should never go into exile, but Hashem had already sworn that He would 'scatter you among the nations'. 2
What did Hashem mean when He said to Moshe "Rav Lach!"
Rashi #1: That the people should not claim that the 'Rav' 1 is so hard whilst the Talmid is so patient as he pleads with Him.
Rashi #2: (He was telling Moshe not to worry, since) Much more reward (than entering Eretz Yisrael) is reserved for him and stored away in the world to come.
See Sifsei Chachamim.
And what are the words "Od ba'DavaR ha'Zeh" referring to?