As you say, 사랑으로 (with love) is common. We never shorten 으로 to 로 as far as I know. That will be very confusing and it doesn't pronounce nicely either.
If the 자막 also said 사랑로, it was probably referring to it as a noun. 로 as a suffix means "street" (태평로 = Taepyeong Street), so it is conceivable to name a street 사랑로 ("love street", "love way"), or use it figuratively for "the way of love". If I google for this word, I see some names like 물사랑로 (Water Loving street, or Waterly Love street?), or a church named 사랑로 교회 (Church of The Way of Love).
"어서 와", "어서 오세요"
They can mean either "come quickly" or "welcome, I'm glad you're here". The intonation is usually quite different between the two - the former sounds demanding and the latter more relaxed.
"유면했었어" => "유명했었어"
유명하다 (유: have, 명: name => has a name) means famous. -ㅆ었어 indicates a far past (past imperfect) like "used to" in English (it has a nuance of "not anymore" compared with the simpler "-ㅆ어" - 유명했어). So the phrases means "(someone) used to be famous". You can think of phrases like "그 남자는 유명한 가수야" (He's a famous singer), "그 여자는 한떄 배우로 유명했다" (She was once famous as an actress), This place used to be famous (이 곳은 옛날에 유명했었다).
* The Naver dictionary lists two words under 유면하다, but they're both so obscure no one would have even heard of them (except the dictionary publishers:-).
tony /misc/Torrents/CLE Phonétique Progressive du Français intermediare/CLE Pho