woosoki

Thanks for the translation, with one suggestion:

Although the word Haneulbeet is combination of haneul (sky) and beet (light), it means sky-colored in Korean, as the word beet as a suffix means "-colored" or "-tinted."

Therefore:

The main character onstage in the skylight => The main character on the sky-colored stage

The lyrics with each girl's part:

(Seohyun) Tell me your wish, I will make it come true
Don't just pray every night at home by yourself
(Taeyeon) Your heart that loves me, your wish that wants to be with me

(Yoona) Stupid baby, I prayed for this too
(Sunny) That you would come to love me

(All) Honey, I cannot believe it
Whenever you're sad, if you just look upon my face
You will suddenly smile joyfully
I can make you happy
I'm perfect for you

(Jessica) I thought many times of the things we could do
When that day comes that we would love each other
(Yuri) When I look now at us walking together holding hands
Nothing else comes to my mind

(Hyoyeon) My sweet baby, just leave it like this
(Tiffany) It's so wonderful with this reason of love

(All) Honey, I am loving you
This greedy and prideful person I am is slowly changing
Suddenly, my heart becomes more open
You make me happy
I'm perfect for you

(Yuri) I have a wish
(Sooyeong) That you would forever be my love
(Taeyeon, Jessica) I will become more caring for you

(Jessica) Oh~ please oh, make my wish come true

(All) Honey, I cannot believe it
Whenever you're sad, if you just look upon my face
You will suddenly smile joyfully
(Taeyeon) I can make you happy
I'm perfect for you

(All) Honey, I am loving you
This greedy and prideful person I am is slowly changing
Suddenly, my heart becomes more open

(Jessica) You make me happy
I'm perfect for you

Love this song

Here's revised romanized Korean lyrics, with changes in italics:

[taeyeon] tolineun mam goma oon mam gadeukhi damaso
[taeyeon] jelyepeun pojang soge (jonhago shipeunde)
[yuri] anilgoya ooseulgo ya ungdoonghan sang sang daemooneh
[yuri] mae il miruneun babo (wae nagat janh ge)

[jessica] neul ootdon moseub neega nae mam hoom chingo
[sunny] jung malo numoo maldo andweneunde

[all] *please baby baby baby geu dae ga nae aneh
[seohyun] numoo do gipi deurowa bo ilga iron nae sujubeun gobaek
[all] baby baby baby salmyo shi dagaga
[sooyoung] jakeun mogsoriro gaka ee noman deulige malhae joolkeh

[yoona] dab dab han mam mianhan mam onjenga jonaejool
[yoona] mae il sahyo ganeun sunmool (jonhago shipeunde)
[tiffany] anilgo ya shireulgoya
[tiffany] geunyang nal pyon han chingu ee sangeun joldae anya (geuromyun ochae?)
[sunny] neul ootneun moseub nimam hoom chigo shipo
[taeyeon] jongmalo numoo deulryo jugo shipo

[all] please baby baby baby geudaega nae aneh
[yuri] numoodo gipi deurowa bo il ga iron nae sujubeun gobaek
[all] baby baby baby sal myo shi dagaga
[yoona] boodeuron noon ooseum euro noye mameh seumyo galgoya

[seohyun] sashil nudo alkol dagagaji mothaneun nal
[Jessica] oneu saenga naege no daga ogo itneungol
[taeyeon] pogeunhan geu poomeuro nal kok anajwo

[all] *please baby baby baby geudaega nae aneh
[yuri] numoo do gipi deurowa bo il ga iron nae sujubeun go baek
[all] baby baby baby sal myo shi dagaga
[yoona] jakeun mogsoriro gaga ee noman deulige malhae joolkeh

[all] please baby baby baby naega geudae aneh
[tiffany] sojoong han sarang maneuro gadeuki chaewo noko shipungolyo
[all] baby baby baby ijeneun geudaeye
[taeyeon] nugodo boorubji anheul gajang yepeun yoja chinguya

baby baby baby

Just a newbie here but here's some suggestions (italicized) for your consideration concerning the chorus part:

I want to walk with you in step, holding your hands
I want to lean on your shoulder and tell you.
"Thank you I Love You I will only give you happiness" Kissing you oh my love
Tomorrow, lying next to me in the warm sunshine
sing me a love song and smile at me
The sweet & happy words "I Love You"

Good translation, but I suggest some minor revisions (italicized) for your consideration:

My trembling heart, my thankful heart
I want to fill it all up
And wrap it up prettily (And give it to you)
No, I'll just smile and laugh because of my silly imagination
A fool that keeps putting it off (Why, that doesn't seem like me..)

Ever smiling, You've stolen my heart
It really does not make any sense

Please baby baby baby You are inside of me
You are so deep within me. Can you see it? My shy confession
Baby baby baby I'm going to you cautiously
With a soft voice, I'll tell it to you closely so only you can hear

A frustrated heart, a sorry heart, when can I show it to you
An ever growing present (I want to give it to you)
No, you won't like it
I'm never going to be more than just one of your comfortable friends (What then?)

Ever smiling, I want to steal your heart
I really want to let you hear it

Please baby baby baby You are inside of me
You are so deep within me. Can you see it? My shy confession
Baby baby baby I'm going to you cautiously
With a soft voice, I'll tell it to you closely so only you can hear

Honestly you should know too why I can't go closer to you
One day, you will come closer to me
Hold me close in your soft hold

Please baby baby baby You are inside of me
You are so deep within me. Can you see it? My shy confession
Baby baby baby I'm going to you cautiously
With a soft voice, I'll tell it to you closely so only you can hear