Why does it say "u'Fduyei Hashem Yeshuvun u'Va'u Tziyon b'Rinah"?
Sanhedrin 110b: This teaches that Dor ha'Midbar will come to the world to come.
Rashi: This is a Tefilah; it is connected to "Uri Uri" (9).
Radak: Like You did, do again for Galus Yisrael. Just like those redeemed passed through Yam Suf and came to their land, so Peduyei Hashem will return from Galus. The prefix Vov in u'Va'u is in place of Ken (so). The same applies to "v'Sifsei Renanos Yehalel Pi" (Tehilim 63:6), "u'Shmu'ah 1 Tovah Tedashen Etzem" (Mishlei 15:30) and many other verses in Mishlei.
Malbim: Even though we are not worthy, and the redemption is not via our deeds, Peduyei Hashem will return via his Chesed and come to Tziyon. Also refer to 10:35:1:2.
In many texts it says Shemu'ah without the prefix Vov. (PF)
What is "Simchah Olam [Al Rosham]"?
Refer to 10:35:2:1-4.
To where to Yagon and Anachah flee?
Refer to 10:35:3:1-2.