What are the connotations of "ve'Hayu lachem he'Arim le'Miklat mi'Go'el"?
Rashi: It means that the Arei Miklat protect the murderer from the closest relative of the victim. 1
Who is permitted to kill him if he found him outside the town.
What are the implications of "ve'Lo Yamus ad Amdo Lifnei ha'Eidah la'Mishpat"?
Rashi (in Bava Kama, 45a): It implies that Beis-Din may only conclude the judgment of the accused in his presence.
Makos, 12a #1: It implies that the Go'el ha'Dam is not permitted to kill the Rotze'ach until he has appeared in Beis-Din - and has been declared guilty.
Makos, 12b #2: It implies that if Beis-Din witnessed a murder, they cannot declare the Rotze'ach guilty until he has appeared before another Beis-Din - and been declared guilty sentenced to death by them. 1
See Torah Temimah note 17.
