ほら does not mean twinkle, though I'm not sure what it does mean
http://dic.yahoo.co.jp/dsearch?p=%E3%81 ... =0&dtype=3
http://dic.yahoo.co.jp/dsearch?enc=UTF- ... &pagenum=1
but there's only one example of にほら on ALC,
http://eow.alc.co.jp/search?q=%E3%81%AB ... B%E3%82%89
君をすきになって行く (i'm (going) to (become) falling in love wit you is correct?)
Yes, that's pretty much 'I'm falling in love with you.' Because it is, the ほら of the previous line could be the exclamation attached to this line, since lines and sentences don't have to match up in poetry.
翳す does not mean 'to shade'
http://dic.yahoo.co.jp/dsearch?p=%E7%BF ... =0&dtype=3
溢れる輝きを力強くありのままに
(The overflowing radiance , stay strong as is it/ I am/we are)?
溢れる輝きを is the object for an implied but dropped する
So, it's 'to keep the brimming radiance as strong as it is now'
(溢れる does literally mean 'overflowing' but in poem, song, and metaphor it's essentially 'brimming' or 'brimming with').
刻まれた時のいみを知る
I know the meaning of time carved?
If 刻まれた時 means 'time with something carved into it', or if it means 'time that has been carved into the shape of something' (which are kind of the same thing), then it's "I know the meaning of the carved time" (but that's horribly unpoetic and almost nonsensical.)
If 刻まれた時 means 'the time it had something carved into it' or 'the time it was carved into the shape of something' then we have, 'I know the meaning of the time when it was carved'.
However, we probably have something from section II,
http://dic.yahoo.co.jp/dsearch?p=%E5%88 ... =0&dtype=3
In which case 刻まれた時 is either 'time that has passed' or 'the time that is indelibly remembered'.
Most likely I think it should be read first as 'I know the meaning of time passed (lost)', and then wonder if it means 'that unforgettable time' and occasionally ponder what metaphorical meanings can be derived from images of carving/engraving something into time or what carvings/engravings the speaker might have done (the time we carved our initials in a tree?)
In other words, this last line is wonderfully ambiguous. What poem is this anyway? I rather like it.
Edit: Oops!
I made a major mistake. That ままに runs right into a verb on the next line. That changes everything. forget that implied する.
考え中...