need your help with cuepoints!

Hi there!
I have a problem, I have to add subtitles to video, though I am new to adobe director and the project is done by another person... It is a cd project in three languages, for one language we have subtitles, but I could not get how developer has done it. There is a video imported as mpeg advance xtra. Cuepoints are added to that video. There are also png files with text in library which have the same names as those cuepoints, and when, for example, video plays in english, subtitles appear there, if in russian, there are no subtitles, and if in third language there are also no subtitles, and I have to fix this problem... To make it more clear here is a piece of code about those cuepoints:

global glang
on cuePassed me, cuePointName1, cuePointName2, cuePointName
sprite(56).member = cuePointName
end

on ExitFrame me
if glang = "eng" then
sprite(56).visible = true
else
sprite(56).visible = false
end if
end

The difficult part for me is to understand how the sprite number 56, which holds subtitles, is connected with the sprite which holds video. How this sprite references those images to appear on the stage, and why this sprite does not reference any cast member (in property inspector in member tab next to member there is sth like this "---") and it does not have any behaviors...

I wish someone could suggest me a way out...
I would really appreciate any help!
Thanks in advance!